UNIVERSITY    OF   CALIFORNIA 

COLLEGE   OF   AGRICULTURE 

AGRICULTURAL    EXPERIMENT   STATION 

BERKELEY,    CALIFORNIA 


FACTORS  INFLUENCING  PERCENTAGE 
CALF  CROP  IN  RANGE  HERDS 


G.  H.  HART  and  H.  R.  GUILBERT 


BULLETIN  458 

September,  1928 


UNIVERSITY  OF  CALIFORNIA  PRINTING  OFFICE 
BERKELEY,  CALIFORNIA 

1928 


Digitized  by  the  Internet  Archive 

in  2012  with  funding  from 

University  of  California,  Davis  Libraries 


http://www.archive.org/details/factorsinfluenci458hart 


FACTORS  INFLUENCING  PERCENTAGE  CALF  CROP 
IN  RANGE  HERDS 

G.  H.  HARTi  and  H.  R.  GUILBERT2 


IMPORTANCE  OF  CALF  CROP  AS  SHOWN   BY  COST  OF 
PRODUCTION    STUDIES 

Recent  studies  in  range  cattle  production  by  the  United  States 
Department  of  Agriculture  and  the  state  experiment  stations  have 
brought  out  two  facts  of  great  importance  to  those  interested  in 
efficient  livestock  production.  First,  they  have  shown  that  the  cost  of 
production  in  beef  cattle  herds  depends  to  a  considerable  extent  upon 
the  number  of  calves  raised  per  hundred  females  of  breeding  age. 
Second,  they  have  shown  great  variations  in  the  number  of  calves 
born  per  hundred  females  of  breeding  age  on  the  different  ranches 
in  the  areas  under  study. 

DATA  OBTAINED   BY  SURVEYS   IN  THE   RANGE  CATTLE  STATES 

The  Federal  work  in  this  field  was  carried  on  by  Klemmedson  and 
Parr.  In  1922  Klemmedson(li)  3  made  a  study  on  41  ranches  in 
Colorado  containing  22,285  cows  and  their  calves.  He  states,  "The 
costs  of  production  differ  widely  with  the  locality  and  with  the  system 
of  management,  both  in  the  same  year  and  from  year  to  year.  There 
is  a  marked  variation  from  ranch  to  ranch  as  the  following  cost 
figures  show.  As  an  illustration  the  five  ranch  herds  shown  below, 
with  no  perceptible  difference  in  range,  feed,  water  facilities,  quality 
of  animals  or  animal  losses,  show  large  differences  in  production  costs 
because  one  ranch  had  a  calf  crop  of  70  per  cent  while  an  adjoining 
ranch  had  a  calf  crop  of  only  36  per  cent." 

The  data  mentioned  above  are  shown  in  table  1. 

On  the  17  prairie  ranches  studied  the  percentage  of  calves  raised 
varied  from  33  to  83  per  cent  with  an  average  of  56  per  cent.  On  the 
21  mountain  ranches  included  in  the  work  the  calf  crop  varied  from 
36  to  76  per  cent  and  averaged  56.7  per  cent.   Seven  of  the  mountain 

1  Professor  of  Animal  Husbandry  and  Animal  Husbandman  in  the  Experiment 

Station. 

2  Assistant  Animal  Husbandman  in  the  Experiment  Station. 

•'{Numbers  in  parentheses  refer  to  references  listed  in  the  back  of  this  pub- 
lication. 


4  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

ranches  kept  the  breeding  herds  under  fenced  pastures  or  fenced 
forest  grazing  land,  where  breeding  could  be  controlled,  and  had  72.7 
per  cent  calf  crop.  The  remaining  17  ranches  running  the  breeding 
herds  on  the  open  forest  range  produced  an  average  calf  crop  of  50.1 
per  cent.  The  authors  were  of  the  opinion  that  this  22.6  per  cent 
difference  in  the  calf  crop  was  due  to  the  difference  in  method  of 
handling  the  herds,  but  nothing  is  stated  regarding  feed  supply  in 
the  two  areas. 

TABLE  1 

Variation  in  Cost  of  Producing  Calves  on  Five  Adjoining  Eanches  in 

Colorado,  1922 


Ranch 
number 

Calf  crop 

% 

Gross  cost 
per  calf 

7 

70 

$32.50 

2 

67 

39.78 

14 

56 

52.02 

40 

51 

45.11 

13 

36 

66.12 

In  1920,  1921,  and  1922  Parr  and  Klemmedson(20)  made  a  similar 
study  in  the  northeastern  range  area  of  Texas  on  15  ranches  contain- 
ing 38,511  cows  and  their  calves.  In  this  work  they  state:  "The  items 
which  enter  into  the  cost  of  producing  a  calf  at  weaning  are  divided 
into  two  groups — operating  costs  and  deductions  from  profits.  The 
prime  production  cost  of  a  calf  is  the  total  operating  cost  divided  by 
the  number  of  calves  produced." 

In  describing  the  breeding  herd  they  state :  ' '  Two-year-old  heifers 
are  included  in  the  cow  herd  in  view  of  the  fact  that  the  prevailing 
practice  is  to  breed  heifers  to  calve  at  two  years  of  age.  Aside  from 
the  ratio  of  serviceable  bulls  to  the  number  of  cows,  range  conditions 
are  an  influencing  factor  in  the  calf  crop.  Scant  range  during  the 
spring  and  summer  invariably  results  in  a  small  percentage  of  calves 
the  next  spring." 

On  the  15  ranches  the  percentage  calf  crop  varied  from  94  per 
cent  on  ranch  No.  6  to  51  per  cent  on  ranch  No.  15,  and  the  operating 
cost  of  production  per  calf  varied  from  $12.49  on  ranch  No.  6  to 
$31.56  on  ranch  No.  13.  They  state:  "Varying  practices  show  their 
effect  in  the  operation  results  and  important  among  them  is  the 
method  of  handling  the  bulls.  On  10  of  the  15  ranches  the  bulls  were 
taken  out  of  the  cow  herd  in  the  fall  for  conditioning  and  were 
returned  to  the  cow  herd  around  June  1  of  the  following  year.  On  the 
other  5  ranches  the  bulls  were  kept  in  the  cow  herd  during  the  entire 


Bul.  458] 


PERCENTAGE    OF    CALF    CROP    IN    RANGE    HERDS 


year.  The  ranches  on  which  the  bulls  were  removed  from  the  cow  herd 
had  a  77  per  cent  average  calf  crop  for  three  years,  and  on  the  ranches 
where  the  bulls  were  not  removed  from  the  cow  herd  the  average  calf 
crop  was  64  per  cent  for  the  same  time.  The  conditioning  of  the  bulls 
was  in  a  measure  directly  responsible  for  a  13  per  cent  increase  in 
the  number  of  calves  dropped.  Uniformity  of  age  of  calves  and  a 
saving  of  feed  in  wintering  cows  are  facts  resulting  from  the  practice 
that  are  real  advantages." 

During  the  years  that  the  above  work  was  being  carried  on  the 
same  authors(21)  also  made  a  similar  study  on  15  ranches  in  north 
central  Texas  and  extended  it  in  1923  to  40  ranches  carrying  65,458 
cows  and  their  calves.  In  those  parts  of  this  area  where  calves  were 
produced  at  unusually  low  costs  there  were  high  calf  crops  and 
vice  versa. 

Under  variations  in  calf  crops,  they  state :  ' '  The  number  of  calves 
per  100  cows  is  the  vital  factor  in  the  cost  of  producing  calves  under 
ranching  conditions.  There  is  a  direct  relationship  between  the  net 
cost  of  calves  raised  and  the  per  cent  calf  crop."  The  figures  bearing 
on  this  point  are  shown  in  table  2. 

TABLE  2 

The  Influence  of  Size  of  Calf  Crop  Upon  the  Net  Cost  Per  Calf 

(43,367  calves  under  study  in  north  central  Texas,  1920  to  1924.) 


Per  cent  of  calf  crop 
(by  groups) 

Number 

of  ranches 

in  each  group 

Number  of 
of  calves 

Net  cost 

per  calf 

(4  yr.  average) 

Per  cent 
of  total 
calves 

30-40 

1 
2 
14 
18 
22 
22 
5 

590 

585 

11,880 

8,020 

10,848 

9,749 

1.695 

$43.92 
49.21 
36.15 
38.88 
28.03 
25.46 
22.15 

1.4 

40-50 

1.3 

50-60 

27.4 

60-70 

18.5 

70-80 

25  6 

80-90  .... 

22.5 

90-100 

3  9 

84 

43,367 

$31.95 

100  0 

In  regard  to  the  much  discussed  question  of  the  number  of  cows 
per  bull  they  made  the  following  statement,  based  on  the  work  in 
this  area: 

"A  study  of  the  range  conditions  in  connection  with  the  calf  crop 
on  15  ranches  upon  which  data  have  been  obtained  for  four  years 
shows  that,  7  ranches,  running  1  bull  to  19  cows,  and  stocked  at  the 
rate  of  10.4  acres  per  cow  unit  in  1922  on  which  range  conditions 
were  below  normal  had  a  calf  crop  of  49.1  per  cent.    Eight  other 


b  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

ranches  running  1  bull  to  22  cows  and  stocking  9.2  acres  per  cow 
unit  on  which  the  range  was  normal  in  1922  had  a  calf  crop  of  80.5 
per  cent  in  1923,  showing  that  the  condition  of  the  range  was  the 
important  factor.  Even  though  the  8  ranches  were  stocked  heavier 
than  the  7  ranches  they  had  a  31.4  per  cent  higher  calf  crop  due  to 
better  range  conditions. 

As  a  rule  there  is  less  variation  in  the  calf  crops  on  the  smaller 
than  on  the  larger  ranches,  due,  in  all  probability,  to  the  fact  that 
the  breeding  herds  on  the  small  ranches  are  generally  maintained  in 
better  condition.  A  higher  percentage  calf  crop  is  generally  obtained 
on  the  smaller  ranches. 

Likewise  a  comparison  of  calf  crops  on  ranches  making  a  practice 
of  breeding  heifers  to  calve  at  two  years  of  age  compared  with  those 
that  breed  to  have  the  first  calf  dropped  at  three  years  shows  less 
than  1  per  cent  difference  in  the  calf  crop  in  favor  of  breeding  heifers 
to  calve  at  three  years  of  age." 

RESULTS    SHOWN    BY   SURVEYS    IN    FAR    WESTERN    STATES 

In  addition  to  the  work  above  reported  by  the  Federal  investi- 
gators in  Colorado  and  Texas,  information  has-  accumulated  in  other 
far  western  states  on  this  subject.  Hilts(12)  in  a  study  of  the  1924 
calf  crop  in  Nevada  found  in  the  northern  district  an  average  crop 
of  66  per  cent  with  a  variation  from  25  to  95  per  cent ;  in  the  central 
district  an  average  of  61  per  cent  with  a  variation  from  25  to  95  per 
cent  and  in  the  southern  district  an  average  of  51.5  per  cent  with  a 
variation  from  25  to  85  per  cent.  Some  cattlemen  obtained  30  calves 
more  per  100  cows  than  others  operating  under  the  same  conditions. 
He  also  observed  that  cows  turned  out  in  good  condition  in  the  spring 
produced  18  more  calves  per  100  than  were  obtained  from  cows  turned 
out  in  poor  condition. 

The  abortion  loss  from  all  causes  was  3  per  cent  in  the  northern 
district;  2.1  per  cent  in  the  central  district  and  1.2  per- cent  in  the 
southern  district  with  a  state  average  of  2  per  cent.  The  contagious 
abortion  loss  in  infected  herds  was  5  per  cent  in  the  northern;  6.8 
per  cent  in  the  central  and  4.5  per  cent  in  the  southern  district,  with 
an  average  of  5.5  per  cent.  It  is,  therefore,  evident  that  abortion  is 
a  minor  factor  in  the  Nevada  area. 

Potter(22)  states,  "The  well  known  veterinary  authority,  Fleming, 
estimates  that  the  average  breeding  efficiency  of  cattle  is  about  78 
per  cent.  The  carefully  managed  herd  will  do  somewhat  better  than 
this  and  will  sometimes  go  as  high  as  85  per  cent  or  90  per  cent.   On 


BlJL,.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  7 

the  other  hand,  however,  the  average  herd  on  the  open  range  will  not 
do  so  well,  the  average  being  about  60  per  cent,  although  with  good 
care  and  good  bulls  an  average  of  65  per  cent  to  70  per  cent  is  obtain- 
able.  This  percentage  largely  determines  the  cost  of  the  calf." 

In  1925,  Potter(23)  states  that  the  percentage  will  vary  greatly  in 
good  and  bad  years.  Also  that  cattle  handled  in  small  pastures  will 
produce  about  10  per  cent  higher  calf  crop  than  range  cattle. 

In  unpublished  data  collected  by  E.  B.  Stanley,  of  the  Arizona 
College  of  Agriculture — on  63  cattle  ranches  in  the  year  1925  an 
average  calf  crop  of  32.14  per  cent  was  obtained.  At  this  particular 
time  the  economic  and  physical  conditions  of  the  range  livestock 
industry  were  at  a  very  low  ebb.  He  stated,  however,  that  it  was  the 
concensus  of  opinion  that  the  average  calf  crop  in  Arizona  will 
approximate  40  per  cent  over  a  period  of  years,  although  a  number 
of  cow  outfits  attained  as  high  as  85  or  90  per  cent  calf  crop  in  1927. 
This  was  to  be  considered  an  exceptional  condition  and  would  be  offset 
to  a  considerable  extent  by  the  drought  years  which  occur  periodically 
in  that  and  adjoining  states. 

In  1927  Walker  and  Lantow32  published  range  cattle  studies 
made  in  1925  on  127  ranches  in  New  Mexico.  The  data  collected 
showed  that  78  per  cent  of  all  losses  on  the  ranches  studied  were  due 
to  starvation.  This  means  that  about  12  out  of  every  100  head  of 
cattle  on  ranches  in  the  state  die  of  starvation,  varying  in  the  differ- 
ent districts  from  5  to  15  head  per  100. 

There  has  been  criticism  directed  against  some  experimental  work 
in  this  country  because  the  animals  were  kept  on  a  restricted  food 
intake.  With  this  type  of  evidence  on  the  range,  one  can  readily  see 
that  there  are  thousands  of  head  of  animals  in  this  country  on  very 
restricted  nutritional  regimes  that  are  not  in  any  experimental  tests. 
It  must  also  be  recognized  that  experimental  animals  may  be  placed 
on  extremely  rigorous  nutritional  regimes  and  yet  not  exceed  that 
which  is  the  common  lot  of  commercial  stock  cattle  herds  in  very  wide 
areas  of  the  semi-arid  southwest  range  area  of  the  United  States 
during  parts  of  practically  every  year. 

The  above  workers  state  that  New  Mexico  is  almost  constantly  in 
the  throes  of  a  drought.  Ranchers  in  planning  future  operations  are 
more  and  more  contemplating  running  just  enough  cattle  to  utilize 
the  grass  during  the  poorest  years.  Feeding  bulls  cottonseed  cake 
during  both  the  winter  months  and  the  breeding  season  appeared  to 
increase  the  calf  crop.  It  was  also  noticed  that  an  increased  calf  crop 
was  obtained  when  the  1924  forage  on  the  range  was  sufficient  or 
when  feeding  was  practiced  with   both   roughage   and   concentrate. 


8  UNIVERSITY   OF    CALIFORNIA EXPERIMENT    STATION 

Feeding  cake  alone  in  the  absence  of  sufficient  forage  did  not  appear 
to  increase  the  calf  crop.  On  all  the  ranches  studied  a  57  per  cent 
calf  crop  was  born  and  a  48  per  cent  calf  crop  was  branded,  thus 
increasing  the  cost  of  production  per  calf  from  $26.80  at  birth  to 
$32.15  at  branding  time.  In  these  studies  it  was  found  that  the  larger 
the  ranch  the  greater  the  cost  of  production  and  the  smaller  the  per- 
centage calf  crop  born  or  branded. 

In  1924  Adams(1)  in  a  survey  on  cost  of  producing  beef  in  Cali- 
fornia, found  that  cattlemen's  statements  of  their  calf  crop  ranged 
from  a  low  of  50  per  cent  to  a  high  of  90  per  cent  and  averaged  for 
the  32  records  67.3  per  cent. 

FAILURE  TO    CONCEIVE    AS    COMPARED   TO    PREMATURE 

DELIVERY 

Failure  to  conceive,  or  expulsion  of  the  fetus  before  it  is  viable 
has  the  same  result  so  far  as  actual  percentage  calf  crop,  is  concerned. 
It  is  readily  appreciated,  however,  that  they  are  fundamentally 
entirely  different  conditions.  In  failure  to  conceive  we  have  a  condi- 
tion in  which  the  female  did  not  come  in  estrum  or  did  not  breed,  or 
having  come  in  estrum  and  having  been  bred,  something  either  on 
the  part  of  the  female  or  of  the  male  prevented  conception.  In  pre- 
mature delivery  all  of  the  essentials  for  the  establishment  of  preg- 
nancy were  existent,  but  after  conception  occurred  some  other  factor 
came  into  play  which  prevented  the  normal  development  of  the  fetus 
and  caused  its  expulsion  before  the  end  of  the  gestation  period. 

In  the  areas  where  low  percentage  calf  crop  has  been  observed 
for  many  years  a  number  of  factors  have  been  assigned  as  the  cause. 

Recently,  with  the  great  amount  of  study  being  made  on  infec- 
tious abortion  and  the  definite  knowledge  that  it  exists  in  range  cattle, 
greater  emphasis  has  been  placed  on  this  as  an  important  factor  in 
calf  crop. 

EVIDENCE  THAT   FAILURE  TO   CONCEIVE    IS  THE   PRINCIPAL 

FACTOR    IN   SUSTAINED    LOW   CALF    CROP 

OVER   WIDE   AREAS 

It  is  true  that  bovine  infectious  abortion  does  attack  range  cattle 
and  may  in  individual  cases  over  one  or  two  seasons  be  the  cause  of 
extremely  low  percentage  calf  crops.  At  one  time  it  was  thought  that 
the  extension  of  this  disease  from  the  dairy  herds  to  the  ranges  would 
be  a  very  serious  permanent  factor  in  the  calf  crop.  However,  expe- 
rience has  shown  that  from  the  standpoint  of  the  individual  herd 


BUL.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  9 

abortion  is  a  self -limiting  disease.  This  is  due  to  the  gradual  acquiring 
of  a  tolerance  or  immunity  to  the  organism  so  that  it  will  cease  to 
produce  its  manifestation  over  a  varying  period  of  time  even  though 
no  special  precautions  are  taken  to  limit  its  ravages.  This  is  mani- 
fested in  range  herds  more  frequently,  and  in  a  shorter  period  of 
time,  than  in  dairy  herds  because  the  latter  are  crowded  together 
in  comparatively  small  quarters,  which  gives  much  better  opportunity 
for  the  spread  of  the  infection.  Very  great  reductions  in  the 
incidence  of  the  disease  have  been  observed  from  one  year  to  the  next. 
Potter (24)  in  his  work  on  range  cattle  in  western  Kansas,  observed 
this  in  herd  after  herd  and  did  not  hesitate  to  predict  the  cessation  of 
the  disease  after  two  years.  The  percentage  of  second-aborters  in 
range  cattle  is  low.  The  continuance  of  the  disease  is  frequently 
carried  on  in  a  low  percentage  by  the  abortion  of  first-calf  heifers. 
These  receive  the  infection  from  adult  cows  which  have  aborted,  and 
which  remain  carriers  and  disseminators  of  the  infection  even  though 
they  no  longer  manifest  any  observable  evidence  of  the  disease. 

Hilts(12)  showed  in  Nevada  that  the  state  average  abortion  loss  from 
all  causes  was  2  per  cent.  In  herds  actually  infected  with  contagious 
abortion  the  premature  births  averaged  5.5  per  cent.  Such  evidence 
shows  clearly  that  the  great  variation  in  calf  crop  extending,  on 
different  ranches  in  the  Nevada  study,  from  25  to  95  per  cent  could, 
under  no  circumstances,  be  entirely  attributed  to  abortion.  This 
evidence,  together  with  that  existent  in  all  of  the  western  range  area, 
shows  that  the  factors  which  prevent  the  establishment  of  pregnancy 
are  the  principal  factors  involved  in  the  greatly  varying  percentage 
calf  crops  over  a  series  of  years. 

There  is,  of  course,  more  than  one  factor  involved  in  failure  to 
conceive.  For  many  years  it  has  been  ascribed  to  methods  of  herd 
management,  and,  recognizing  the  broad  field  that  such  a  term  covers, 
it  is  correct.  Within  this  general  statement  are  several  factors  to  be 
considered  however,  among  which  may  be  mentioned  a  definite  breed- 
ing season,  proper  proportion  of  males  and  females  and  the  plane  of 
nutrition  of  the  animals. 

There  are  a  number  of  advantages  in  having  a  definite  breeding 
season  in  range  cattle  herds  and  this  should  always  be  practiced  when 
possible.  It  allows  for  conditioning  of  bulls  in  the  non-breeding  sea- 
son, uniformity  of  age  of  calves,  limiting  range  of  females  during 
breeding  season  so  they  will  have  better  opportunity  to  come  in  contact 
with  males  during  estrum,  and  definite  knowledge  as  to  the  non- 
pregnancy  of  cows  which  have  not  calved  in  any  one  year.  Proper 
proportion  of  males  to  females  is  of  course  a  factor  to  be  reckoned 


10  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

with,  although  it  may  vary  considerably,  other  conditions  being 
favorable,  without  markedly  changing  the  results.  Bulls  should  be 
active  and  in  a  good  state  of  nutrition.  Cows  should  not  be  scattered 
in  small  groups  or  singly  over  wide  areas  as  under  such  conditions 
estrum  may  occur  several  times  without  their  coming  in  contact  with 
a  male.  A  number  of  years  ago  when  Texas  fever  tick  eradication 
was  going  on  in  California,  range  cattle  were  rounded  up  and  dipped 
every  25  to  30  days.  Evidence  developed  that  the  procedure  increased 
the  calf  crop  simply  from  the  fact  that  bulls  were  brought  in  close 
contact  with  all  the  cows  at  30-day  intervals.  It  must  be  recognized, 
however,  that  destroying  the  ticks  also  had  the  effect  of  increasing 
the  plane  of  nutrition  of  the  animals.  It  is  quite  possible  that  a 
proportion  of  less  than  1  bull  to  15  breeding  females  may  be  a  limiting 
factor  in  calf  crop  under  unfavorable  conditions.  On  the  other  hand, 
with  otherwise  favorable  conditions,  1  bull  to  30  females  may  be 
sufficient. 


EXPERIMENTAL   EVIDENCE   THAT   FAILURE   TO    CONCEIVE    IS 

PARTLY   BASED   ON   PLANE   OF    NUTRITION   AND 

MINERAL    METABOLISM 

The  condition  of  nutrition  of  animals  has  an  important  bearing  on 
the  development  of  estrum.  It  has  long  been  observed,  for  example, 
in  range  cattle  that,  during  unfavorable  years  when  feed  is  poor  and 
weather  conditions  bad,  causing  mature  non-pregnant  cows  to  become 
very  thin,  no  estrum  is  noticed  until  feed  conditions  are  such  that  the 
animals  begin  to  improve  physically  even  though  many  months  are 
required  for  this  change  to  occur.  If,  therefore,  the  year  has  been 
one  of  severe  drought  the  cattle  become  very  thin  and  some  cases  of 
death  from  actual  starvation  may  occur.  The  following  fall  or  winter 
may  be  one  of  copious  rainfall  and  open  weather  conditions,  resulting 
in  plenty  of  feed  and  constituting  a  so-called  good  year.  Under  such 
conditions  it  will  take  a  considerable  part  of  this  good  year  for  the 
animals  to  get  back  into  a  sufficiently  high  plane  of  nutrition  for  the 
normal  development  of  the  estrous  cycle  followed  by  breeding  and 
the  nine  months  gestation  period,  thus  running  into  the  second  year 
following  the  drought  before  the  normal  or  high  calf  crop  is  obtained. 

Evans(G)  has  shown  that  in  the  white  rat  certain  nutritive  regimes 
may  permit  growth  to  occur  and  still  interfere  with  or  prevent  the 
normal  rhythmic  functioning  of  the  ovary.  This  mechanism  was 
shown  to  be  influenced  by  qualitative  and  quantitative  undernutri- 
tion.   In  a  study  of  the  normal  appearance  of  the  first  cycle  in  the 


BUL.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  11 

particular  colony  of  rats  with  normal  diets  he  found  that  in  80  per 
cent  of  the  animals  the  first  estrus  occurred  between  37  and  55  days 
with  an  average  of  47  days.  With  McCollum's  standard  diet  I,4  he 
limited  the  intake  of  this  food  by  the  animals  so  as  to  create  partial 
starvation.  One  group  of  animals  was  kept  at  a  weight  level  of  200 
grams,  a  second  group  at  125  to  150  grams  and  a  third  group  at  60 
to  85  grams.  For  the  first  group  the  diet  had  to  be  reduced  only 
slightly  over  that  given  the  controls,  while  it  had  to  be  reduced  to 
two-thirds  for  the  second  group  and  to  one-half  for  the  third  group. 
The  animals  in  the  latter  group  did  not  exhibit  an  estrous  cycle  in 
375  days.  In  the  second  group,  8  of  the  10  animals  eventually  exhib- 
ited estrum.  Its  first  appearance  varied  from  116  to  332  days  and 
averaged  210  days.  Two  of  the  animals  in  this  group  did  not  develop 
estrum  during  the  entire  year.  Even  in  the  first  group  ovulation  was 
seriously  affected.  There  was  delay  in  the  appearance  of  the  first 
estrum  from  the  50th  to  the  135th  day  with  an  average  appearance 
on  the  67th  day,  as  compared  to  maturity  at  the  50th  day  in  normal 
controls.  It  was,  therefore,  evident  that  a  general  or  quantitative 
undernutrition  depending  on  degree  prevented  or  postponed  the 
attainment  of  sexual  maturity. 

When  animals  were  placed  on  carbohydrate-free  diets,  with  pro- 
tein neither  high  nor  low,  they  grew  normally  and  no  significant 
injury  to  the  sex  physiology  was  produced.  With  diets  deficient  in 
salts  it  was  evident  that  the  sex  impairment  was  much  in  excess  of 
the  impairment  of  growth.  Without  being  able  to  explain  this  con- 
dition, the  observation  was  made  that  depletion  of  salts  is  inimical 
not  only  to  skeleton  growth  but  to  the  normal  rhythm  of  ovulation. 

In  general  it  was  concluded  that  underfeeding  affects  time  of 
maturity  and  ovulation  history.  The  maintenance  of  ovulation 
rhythms  and  the  capacity  to  have  young  constitute  a  more  exacting 
test  of  a  sound  physiology  than  does  growth  alone. 

There  are  some  areas  in  the  western  range  country  such  as  southern 
Nevada  where  plant  growth  is  so  restricted  by  soil  and  weather 
conditions  that  the  production  of  one  calf  every  two  or  even  three 
years  is  considered  the  average  result  to  be  expected. 

4  McCollum's  Diet   I  consists  of  the  following  ingredients:  % 

Casein    (uncooked)    15.0 

Whole  milk  powder  10.0 

Sodium  chloride  8 

Calcium  carbonate  1.5 

Butter    5.2 

Whole  wheat    (ground) 67.5 

100.0 


12  UNIVERSITY   OF    CALIFORNIA EXPERIMENT    STATION 

It  is  now  generally  recognized  that  minerals  play  an  important 
part  in  animal  nutrition  and  that  calcium  and  phosphorus  are  two  of 
the  very  important  minerals  that  are  found  in  the  animal  body. 
These  elements  are  important  in  the  formation  of  the  skeleton  but 
exist  in  more  or  less  constant  proportion  in  the  circulating  blood  and 
are  given  off  in  very  definite  and  sizable  quantities  in  the  milk.  It 
must  be  recognized  as  conceivable,  therefore,  that  animals  may  get 
sufficient  food  to  supply  their  energy  and  protein  requirements  with- 
out getting  sufficient  minerals,  particularly  calcium  and  phosphorus, 
to  maintain  their  normal  mineral  metabolism  requirements.  This  is 
quite  definitely  recognized  and  understood  to  exist  in  iodine  defi- 
ciency where  various  symptoms  are  observed  in  human  beings  and 
animals  which  are  receiving  a  normal  intake  of  food  for  energy  and 
protein  requirements.  In  animals  this  condition  is  manifested  by 
hairless  and  goitrous  offspring.  Evidence  is  accumulating  in  various 
parts  of  the  world  that  a  variety  of  conditions  may  be  manifest  under 
prolonged  subnormal  intake  of  calcium  and  phosphorous.  Some  of 
these  conditions  are  probably  manifested  in  the  function  of  repro- 
duction and  milk  secretion. 

The  most  exhaustive  experimentation  on  this  subject  has  been 
carried  out  by  Theiler(26)  and  his  associates  in  their  studies  of 
lamsiekte  or  parabotulism  in  cattle  on  the  South  African  veld.  This 
is  a  disease  caused  by  the  toxin  of  the  parabotulinus  organism  which 
is  contained  in  decomposing  tissues  on  bones  eaten  by  cattle  suffering 
from  osteophagia  or  bone  craving.  The  depraved  appetite  causes  the 
cattle  to  ingest  carcasses  of  small  animals  or  green  bone  on  the  veld 
containing  the  organism  and  its  toxin  which  is  the  direct  cause  of  the 
disease.  The  indirect  cause,  however,  is  the  depraved  appetite  which 
the  work  of  Theiler  from  1917  to  1921  caused  him  to  believe  to  be  due 
to  the  lack  of  phosphorus  in  the  vegetation. 

However,  this  author  states:  " Incidentally  it  may  be  remarked 
that  a  high  ratio  of  lime  to  phosphorus  in  the  mineral  matter  of  a 
plant  may  possibly  have  a  similar  effect  to  a  low  absolute  percentage 
of  phosphorus,  and  we  are  yet  prepared  to  substitute  an  excess-lime 
hypothesis  for  a  phosphorus-deficiency  theory.  We  do  not  yet  wish 
to  bind  ourselves  to  any  one  single  explanation  of  the  observed  facts, 
but  wish  to  avoid  adopting  too  simple  an  explanation  for  what  may 
ye1  turn  out  to  be  a  complicated  business." 

Further  extensive  experiments  were  carried  out  by  Theiler,  Green 
and  DuToit(27)  to  determine  the  extent  to  which  phosphorus  entered 
as  an  economic  factor  in  beef  production,  with  striking  results  pub- 
lished in  1924  from  which  the  following  is  quoted : 


BUL.  458]  PERCENTAGE   OF   CALF   CROP   IN   RANGE   HERDS  13 

"Phosphorus  is  unquestionably  a  limiting  factor  in  the  growth 
rate  of  cattle,  and  a  dominating  factor  in  the  maintenance  of  live- 
weight  under  ordinary  conditions  of  veld  grazing,  so  that  the 
nutritional  aspects  of  the  investigations  now  altogether  overshadow 
the  original  problem  of  disease.  Since  the  areas  over  which  the  nutri- 
tional factors  apply  are  far  wider  than  those  over  which  lamsiekte 
occurs,  the  annual  financial  gain  to  the  stock-raising  industry  in  the 
future  can  easily  be  made  far  to  exceed  the  annual  financial  losses 
from  lamsiekte  in  the  past.  Indeed,  by  focusing  attention  upon 
specific  nutritional  deficiencies  of  South  African  veld,  the  disease  can 
almost  be  said  to  have  been  'a  blessing  in  disguise.' 

"Increase  of  milk  yield  of  cows,  better  calves  at  birth,  more  rapid 
growth  of  young  stock,  and  superior  fattening  of  adult  cattle,  all 
follow  simple  bone-meal  feeding,  and  agricultural  propagandists 
might  well  carry  the  phrase  'Bone-Meal  for  Beef  as  a  slogan  cry  over 
all  the  phosphorus  deficient  areas  of  the  Union." 

In  South  Africa,  phosphorus  deficiency  is  a  general  characteristic 
of  the  soils  over  wide  areas.  The  chain  of  evidence  in  that  country 
begins  with  poor  soil  and  ends  with  poor  beef.  Pica  or  depraved 
appetite  was  so  common  that  the  South  African  farmer  had  observed 
it  all  his  life  and  considered  it  normal.  Theiler  and  his  associates 
brought  out  the  fact  that  osteophagia  means  consistently  poor  beef. 
Bone  meal  fed  in  quantity  to  stop  osteophagia  did  not  however  fur- 
nish an  optimum  of  phosphorus  for  maximum  growth  and  fattening. 
For  example,  in  three  calves,  one  fed  no  bone  meal,  one  just  enough  to 
prevent  osteophagia  and  a  third  fed  excess,  the  gains  in  weight  over 
a  period  of  16  months  amounted  to  166  pounds,  295  pounds  and  352 
pounds,  respectively.  In  regard  to  the  per  cent  calf  crop  Theiler 
et  al.(30)  state:  "Of  the  cowrs  receiving  the  bone  meal  ration,  80  per 
cent  calved  normally — a  fair  calf  crop  when  the  varying  age  and 
character  of  the  herd  is  taken  into  consideration.  Of  the  control  cows 
only  51  per  cent  calved."  The  investigators  definitely  showed  that 
phosphorus  could  be  supplied  in  the  form  of  wheat  bran,  bone  meal, 
sodium  phosphate  or  phosphoric  acid  to  produce  the  desired  results. 
In  the  last  form,  however,  it  tended  to  disturb  the  base  acid  equilib- 
rium of  the  body  and  was  used  experimentally  to  prove  that  phos- 
phorus was  the  element  lacking,  rather  than  as  the  best  practical 
means  of  furnishing  this  element.  Bone  meal  was  established  as  the 
best  and  cheapest  form  in  which  to  supply  the  phosphorus. 

In  one  series  of  experiments,  chalk  was  given  to  a  group  of 
animals  but  they  maintained  their  craving  for  bone  and  in  the  latter 
part  of  the  period  seemed  to  manifest  increased  osteophagia.    There 


14  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

had  been  no  evidence  of  deficiency  of  lime  in  the  vegetation  of  the 
area  and  the  practice  of  mixing  lime  with  bone  meal  was  probably 
contraindicated  because  of  the  possibility  of  an  increased  amount  of 
lime  over  that  contained  in  the  bone  meal  decreasing  the  availability 
of  food  phosphorus  during  digestion.  Attempts  at  supplying  the  soil 
with  phosphate  fertilizer  (500  pounds  to  the  acre,  using  super- 
phosphate) were  successful  but  it  was  not  a  practical  procedure  on 
account  of  expense.  Where  bone  meal  was  fed  to  the  cattle  directly, 
results  were  quicker,  costs  less  and  still  a  high  percentage  of  the 
ingested  material  passed  out  with  the  feces  and  thus  gradually  added 
soil  fertilizer.  Their  work  showed  also  that  sheep  were  susceptible 
to  phosphorus-deficient  vegetation  but  that  this  species  of  animals 
could  be  handled  in  areas  where  cattle  were  unprofitable.  Sheep 
showed  osteophagia  in  a  very  slight  degree  which  could  easily  go 
unrecognized,  but  at  the  same  time  were  improved  by  bone  meal 
feeding  given  in  the  amount  of  2  ounces  per  week  with  an  equal 
weight  of  salt  in  the  form  of  a  lick. 

In  the  feeding  of  bone  meal  to  cattle  in  these  areas  the  dose 
varied — one  ounce  for  an  old  ox,  2  ounces  for  a  steer  or  heifer,  and  5 
ounces  for  a  lactating  cow,  fed  every  day  except  Sunday.  In  some 
cases  where  this  was  impractical  feeding  three  times  weekly  gave  very 
good  results.  Feeding  at  less  frequent  intervals  they  found  to  be  of 
much  less  value  often  doing  very  little  good  at  all.  Weekly  feeding 
of  the  material  failed  to  prevent  osteophagia  irrespective  of  the  dose 
given.  The  interesting  question  of  whether  the  cattle  supplied  with 
bone  meal  thus  making  increased  gains  did  so  as  a  result  of  eating 
more  feed  or  by  better  utilization  of  the  same  amount  of  food,  was 
studied  and  answered  as  follows: 

"  (1)  The  cattle  receiving  bone-meal  eat  more  hay,  increase  more 
in  weight,  and  lose  their  osteophagia.  For  the  first  three  months  the 
controls  retain  their  osteophagia,  gain  only  30  lb.  per  head  in  weight, 
and  eat  from  60  lb.  to  80  lb.  of  hay  per  head  per  week,  or  about  10 
lb.  of  hay  per  day  in  addition  to  the  2  lb.  of  Fanko.  The  cattle  receiv- 
ing bone-meal  promptly  lose  their  craving,  eat  90  lb.  to  100  lb.  of 
hay  per  week,  or  about  4  lb.  more  per  day,  and  gain  110  lb.  per  head 
in  weight — practically  four  times  as  much  as  the  controls  receiving 
no  bone-meal. 

"  (2)  At  this  point  (October,  1922),  the  experiment  was  'crossed,' 
in  order  to  make  quite  sure  of  excluding  potential  idiosyncratic 
differences  between  the  two  groups,  i.e.,  the  bone-meal  was  taken 
away  from  one  lot  and  given  to  the  other  lot.  The  effect  was  very 
striking.    Within  a  month  the  osteophagia  curves  and  hay  consump- 


BUL.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  15 

tion  curves  cross,  i.e.,  the  osteophagia  returns  and  the  food  consump- 
tion diminishes  in  the  lot  from  which  the  bone-meal  was  taken  away ; 
while  osteophagia  disappears  and  food  intake  rises  in  the  lot  to  which 
the  bone-meal  ration  was  transferred. 

"The  weight  curves  respond  in  the  same  direction,  and  within 
four  months,  the  previously  inferior  controls  have  not  only  made  up 
their  leeway  of  80  lb.  but  have  actually  surpassed  the  lot  deprived  of 
bone-meal." 

Evidence  was  developed  that  animals  lacking  phosphorus  actually 
consumed  food  in  considerable  excess  over  that  required  for  mainte- 
nance but  the  extra  ration  served  no  useful  purpose. 

In  a  later  publication  Theiler  et  al(28)  show  that  the  seasonal 
limits  of  the  absolute  daily  intake  of  phosphoric  oxide  range  from 
about  38  grams  early  in  November  to  below  11  grams  in  June  on  the 
affected  area  in  that  country.  The  former  figure  represents  sufficient 
for  ordinary  requirements  except  high  milk  production  but  the  latter 
is  below  that  at  which  marked  osteophagia  develops.  The  average 
physiological  limit  for  development  of  osteophagia  is,  therefore,  indi- 
cated at  about  27  grams  phosphoric  acid  in  the  day's  grazing  for 
cattle  of  about  1000  pounds  live  weight. 

In  the  areas  under  consideration  the  cattle  live  for  ten  months  of 
the  year  at  a  very  low  line  of  phosphorus  metabolism  and  have  crav- 
ing as  the  manifestation  of  this  nutritional  deficiency. 

South  Africa  is  not  the  only  part  of  the  world  where  bone  craving 
is  manifested  in  livestock.  In  Norway,  there  exists  a  high  incidence 
of  a  different  condition  in  cattle  known  as  osteomalacia  which  has 
been  studied  extensively  for  many  years  and  the  work  reviewed  by 
Tuff.(31)  While  the  exact  nature  of  this  trouble  is  still  not  fully  under- 
stood in  all  particulars  it  has  been  rather  definitely  established  that 
the  principal  underlying  factor  is  deficiency  of  the  mineral  elements 
of  the  food.  In  South  Africa  phosphorus  was  the  only  element  lacking 
while  in  Norway  calcium  was  definitely  deficient  and  probably  also 
phosphorus  which  accounts  for  the  entirely  different  manifestation. 
Tuff  also  mentions  the  importance  of  the  proportion  between  acid  and 
base  equivalents  in  the  total  foodstuffs  and  the  proportion  between 
the  various  metal-ions  in  the  inorganic  salts  in  the  food  which  he 
states  are  of  the  very  greatest  importance  for  a  normal  metabolism 
of  minerals. 

The  disease  is  more  frequently  manifested  during  a  year  of 
drought  and  the  year  following. 

In  Aust-Agder,  Norway,  in  1862  it  was  reported  that  the  disease 
appeared  in  certain  forms  every  year  and  it  was  found  that  during 


16  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

winter  these  cattle  were  fed  chiefly  hay  and  straw.  When  this  forage 
was  examined  chemically  in  1878  the  ash  content  was  found  to  be 
very  low — 2.6  per  cent  or  two-fifths  of  the  normal  in  good  hay.  The 
percentage  of  lime  and  phosphoric  acid  was  only  one-third  of  normal. 
Throughout  the  winter  in  these  districts  in  Norway  it  had  long 
been  the  custom  for  bones  from  housekeeping  to  be  kept  and,  together 
with  those  sometimes  brought  from  districts  where  the  disease  did 
not  occur,  were  crushed  and  fed  to  the  cows  during  the  summer.  This 
treatment  was  universally  used  in  the  most  pronounced  affected  dis- 
tricts and  without  it  the  livestock  perished.  In  those  districts  an 
interesting  observation  in  sheep  was  pronounced  wool  eating  with 
rachitic  embryos  some  of  which  had  deformities.  Bony  enlargements 
around  the  joints  were  also  frequent  in  cattle  and  horses.  When  only 
hay  and  straw  were  fed  during  the  winter  and  no  commercial  fer- 
tilizer used  the  disease  appeared  at  all  seasons.  With  stronger  winter 
feeding  including  concentrates,  and  commercial  fertilizer  on  the  tilled 
land  supplying  the  winter  fodder,  the  number  of  cases  during  winter 
and  spring  was  reduced.  Experience  showed  that  the  best  means  of 
preventing  and  of  curing  the  disease  was  to  supply  the  cattle  with 
crushed  bones.  It  was  common  to  find  the  condition  in  one  district 
with  a  sharply  defined  boundary  from  an  adjoining  district  where  it 
never  occurred.  This  points  to  the  condition  of  the  soil  as  the  primary 
cause  of  the  disease,  which  was  in  fact  established  by  Kolderup  and 
Aarstad,  and  cited  by  Tuff.(3l)  They  found  a  rocky  substratum  con- 
taining 0.002  per  cent  phosphoric  acid  in  the  affected  district  and  a 
substratum  containing  2  per  cent  of  phosphoric  acid  in  the  unaffected 
areas.  The  percentage  of  lime  in  both  types  of  rock  was  high.  An 
analysis  of  the  loose  soil  and  of  the  hay  that  grew  on  it  showed  both 
to  be  considerably  poorer  than  normal  in  both  phosphoric  acid  and 
lime.  Thus  the  hay  in  the  affected  area  showed  .36  per  cent  CaO  and 
.15  per  cent  P205  (phosphorus  pentoxide)  as  compared  to  .88  per  cent 
and  .44  per  cent  respectively  in  the  unaffected  area.  With  this  prog- 
ress of  reduced  intake  of  calcium  and  phosphorus,  symptoms  of  the 
disease  appear  as  deformity  of  the  skeleton,  cramp  in  the  muscles, 
disturbance  of  the  brain,  reduced  fertility,  anemia;  and  finally  a 
complete  cachectic  condition,  and  fracture  of  bones.  Affected  animals 
have  a  reduced  appetite  and  a  craving  to  eat  abnormal  substances. 
Tuff(31)  states,  "Even  for  a  normal  continuation  of  the  stock  the 
existence  in  the  food  of  sufficient  mineral  substance  is  of  the 
greatest  importance.  Thus  it  is  generally  observed  in  certain  districts 
in  Norway  that  years  of  osteomalacia  are  followed  by  periods 
of  barrenness,  a  number  of  the  animals,  especially  the  heifers,  showing 


BlTL.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  17 

no  signs  of  heat  during  the  latter  part  of  the  winter  and  in  the  spring. 
They  do  not  grow  sexually  normal  and  consequently  can  not  breed  till 
after  they  have  been  on  the  pasture  for  part  of  the  summer.  Some 
stocks  which  have  been  very  badly  attacked  have  to  undergo  treat- 
ment with  preparations  of  lime  and  phosphoric  acid  before  the  gener- 
ative organs  can  once  more  function  normally.  During  the  war,  with 
its  dearth  of  fodder,  similar  observations  were  made  in  Germany." 
The  work  of  Emmerich  and  Loew(5)  on  experimental  animals  is 
cited  as  evidence  of  the  functioning  of  the  reproductive  organs  being 
dependent  on  a  sufficient  supply  of  necessary  minerals.  These  inves- 
tigators by  giving  calcium  chloride  in  the  feed  of  mice,  guinea  pigs 
and  rabbits  demonstrated  that  these  animals  not  only  had  more  young 
at  each  litter  but  also  had  more  litters  per  year  than  the  check 
animals. 

In  further  substantiation  of  the  relation  of  nutrition  to  repro- 
duction some  very  interesting  data  have  been  collected  on  wild 
animals  in  their  native  habitats  by  Julian  Huxley. (13)  Reference  is 
made  to  the  excessive  multiplication  of  field  mice  in  the  San  Joaquin 
Valley,  California,  in  1927.  Presumably  due  to  favorable  environ- 
mental factors  a  similar  plague  occurred  in  Scotland,  in  1892-93. 
These  plagues  are  sometimes  accompanied  by  great  gatherings  of 
birds  which  prey  upon  the  mice.  In  1892,  in  Scotland,  the  supply 
of  food  for  the  short-eared  owls  was  so  great  that  they  prolonged 
their  breeding  season  into  November  and  even  that  late  in  the  year 
produced  broods  much  larger  than  normal.  Nevada  was  visited  by  a 
mouse  plague  in  1907  and  it  was  estimated  that  mouse-eating  birds 
and  mammals  gorging  on  the  mice  killed  over  a  million  of  them  per 
month  and  yet  their  numbers  continued  to  increase.  Huxley  asks  the 
question,  ''Why  these  sudden  outbursts  of  generative  energy  on  the 
part  of  rodents  ? ' '  and  answers, ' '  That  is  a  problem  for  animal  ecology, 
the  branch  of  biology  which  might  be  called  scientific  natural  history 
— the  study  of  animals  in  nature  and  their  relations  with  their 
environment  and  with  other  animals  and  plants.  The  first  thing  the 
ecologist  discovers  is  that  the  plagues  are  not  such  isolated  phenomena 
as  at  first  sight  might  appear.  They  are  merely  exaggerations  of  one 
part  of  a  regular  cycle.  All  small  rodents  appear  to  have  the  life  of 
the  species  strung  on  a  curve  of  numerical  ups  and  downs,  a  cycle  of 
alternating  abundance  and  scarcity." 

The  lemming  of  Scandinavia  is  cited  as  the  best  known  example 
of  cyclical  abundance.  This  animal  of  the  mountains  of  Southern 
Scandinavia  becomes  so  abundant  every  few  years  that  the  young 


18  UNIVERSITY   OF    CALIFORNIA EXPERIMENT    STATION 

animals  set  off  on  migrations  in  all  directions  in  enormous  numbers. 
If  they  come  to  the  sea  they  enter  the  water  and  swim  out  until  they 
drown,  the  coast  becoming  strewn  with  their  corpses.  Other  sorts  of 
animals  show  the  same  rise  and  fall  in  numbers  among  which  are 
cited  the  crossbill  bird  of  the  pine  forests  of  central  Europe,  the 
Pallas  sand  grouse  of  the  steppes  and  deserts  of  central  Asia.  Very 
interesting  data  were  obtained  from  the  Hudson  Bay  Company,  which 
has  kept  records  since  1825  of  the  number  of  skins  of  the  various 
kinds  of  fur  bearing  animals  brought  in  each  year  by  their  trappers. 
These  show  cycles  of  abundance  and  scarcity  in  muskrat,  Canadian 
rabbit,  skunk,  fisher,  mink,  wolverene,  marten,  lynx,  red  fox  and 
Arctic  fox.  The  record  for  lynx,  for  example,  varies  from  30,000  to 
70,000  at  the  peak  to  below  5,000  for  the  depressions.  The  very  large 
numbers  are  obtained  because  the  animals  are  reproducing  faster. 
For  example,  the  Canadian  rabbit  in  bad  years  will  produce  only 
one  brood  of  about  three  young,  while  in  good  years  it  will  produce 
two  or  three  broods  and  eight  or  ten  young  in  each  brood.  Condi- 
tions favorable  for  the  growth  of  plants  will  result  in  favorable  food 
supply  and  increase  in  the  small  herbivorous  animals,  and  these  in 
turn  by  furnishing  food  supply  to  the  carnivorous  animals,  will  cause 
an  abundance  of  these  species.  Huxley (13)  states  "We  know  of  no 
single  case  of  an  animal  changing  its  reproductive  capacity,  whether 
number  of  broods  per  year,  or  number  of  young  per  brood,  so  long  as 
it  is  kept  under  really  uniform  conditions,  while  we  know  of  a  great 
many  cases  in  which  improved  conditions  of  temperature,  food,  etc., 
do  bring  about  an  increase  in  reproductive  output." 

In  1927  Theiler,  Green  and  Du  Toit(29)  published  recent  studies 
on  minimum  mineral  requirements  in  cattle.  In  this  paper  they 
discuss  the  prevailing  views  on  the  question  of  relative  proportions 
of  mineral  elements  and  divide  them  into  three  groups. 

"(a)  The  older  view  that  the  ratio  of  mineral  constituents  in  a 
diet  is  of  little  consequence  provided  the  total  amount  of  each  essen- 
tial is  adequate;  a  sort  of  'Law  of  the  Minimum'  applied  to  animal 
nutrition. 

(b)  An  extreme  modern  view  that  the  ratio  is  of  dominant 
importance  and  may  be  responsible  for  nutritional  disorders  even  if 
each  constituent  is  singly  present  in  sufficient  amount. 

(c)  The  intermediate  view  which  considers  the  absolute  intake  as 
of  primary  importance,  but  also  emphasizes  the  aspect  of  optimum 
relative  proportions,  and  the  influence  of  one  mineral  constituent 
upon  the  absorption  and  utilization  of  another." 


BUL.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  19 

These  workers  rather  regard  the  current  emphasis  on  mineral 
balance  as  exaggerated  and  regard  the  physiological  capacity  of  the 
animal  to  adjust  itself  to  varying  ratios  as  being  much  greater  than 
credited  by  many  authors.  In  their  experiments  they  deliberately 
attempted  to  subject  their  experimental  cattle  to  fairly  extreme  varia- 
tions of  ratios.  A  diet  was  given  consisting  of  3%  pounds  of  hay, 
poor  in  minerals,  and  as  much  Fanko  as  they  would  eat  with  2  ounces 
of  blood  meal  to  insure  sufficient  iron  and  to  vary  the  protein  moiety. 
Fanko  is  a  cereal  flake  breakfast  food  consisting  of  the  rolled  endo- 
sperm of  maize,  of  high  energy  value  and  fair  protein  content  but 
very  low  in  mineral  constituents.  To  this  basal  ration  varying  mineral 
supplements  were  added  in  the  different  groups  of  cattle  such  as 
sodium  chloride,  potassium  chloride,  bone  meal,  chalk,  and  wheat 
bran  for  its  phosphorus  content.  One  group  as  a  check  on  the  vitamin 
factor  had  young  fresh  green  forage  added.  Eight  experiments,  on 
16  heifers  one  year  old  when  the  experiment  started,  were  carried  out 
over  the  period  from  September,  1924,  to  December,  1926.  The  work 
showed  that  mineral  requirements  for  growth  are  higher  in  the  case 
of  phosphorus  than  in  the  case  of  calcium  and  a  ratio  of  P20.  to  CaO 
so  high  as  three  to  one  is  not  necessarily  disadvantageous.  Certain 
observed  abnormalities  in  calving  they  did  not  attempt  to  explain  but 
with  phosphorus  deficiency,  definitely  abnormal  calves  wrere  born. 
They  also  showed  that  styfsiekte,  a  disease  of  South  Africa,  similar 
to  what  European  literature  describes  as  osteomalacia,  wTas  due  to 
lack  of  phosphorus.  Vitamin  deficiency  of  the  diets  had  no  adverse 
effects.  They  also  showed  that  excess  of  basic  over  acidic  constituents 
of  a  diet  is  not  necessary  and  that  cattle  can  grow  normally  to  full 
adult  weight  when  the  usual  alkaline  reaction  of  the  urine  is  shifted 
to  the  acid  side. 

It  is  logical  to  consider,  with  these  definite  findings  in  different 
parts  of  the  world,  that  in  all  probability  similar  conditions  might 
exist  among  domestic  livestock  in  various  parts  of  this  country  with 
its  variable  rainfall,  soil  conditions,  etc.  Recent  years  have  definitely 
shown  this  to  be  the  case.  Along  the  coastal  plains  of  Texas,  so-called 
loin  disease  and  creeps  have  existed  in  the  cattle  and  have  been  under 
observation  for  some  years.  In  the  range  cattle  of  this  area  about  75 
per  cent  develop  the  bone  chewing  habit.  Experiments  with  the 
feeding  of  bone  meal  were  carried  out  by  Schmidt(26)  as  a  part  of  the 
investigations  into  the  nature  and  prevention  of  loin  disease.  He  also 
found  varying  degrees  of  bone  chewing,  some  animals  eating  only  sun 
bleached  bone,  while  others  would  take  foul  smelling  ones  with  putrid 
meat  still  clinging  to  them.    This  was  such  a  common  condition  in 


20  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

this  area  that  it  did  not  arouse  the  curiosity  of  the  owners.  In  many 
cases  the  habit  existed  in  cattle  in  such  a  satisfactory  condition  of 
flesh  that  one  would  not  consider  it  to  be  caused  by  a  craving  for 
anything  lacking  in  the  feed.  Animals  that  were  fed  bone  meal 
eventually  lost  the  bone  chewing  habit  although  in  some  cases  five 
months  or  longer  were  required  to  do  this.  In  general  it  was  found 
that  the  more  bone  meal  an  animal  could  eat  regularly  the  quicker  the 
habit  disappeared. 

The  animals  fed  bone  meal  and  salt  passed  the  winter  in  much 
better  condition  than  the  controls.  With  the  advent  of  spring  the 
difference  was  even  more  marked.  The  cows  receiving  the  material 
became  sleek  and  put  on  flesh  much  sooner  than  the  controls  and  soon 
did  not  look  like  the  same  cattle  of  the  previous  summer.  When 
difficulty  was  experienced  in  getting  the  animals  to  eat  sufficient  bone 
meal  it  was  given  in  a  mixture  with  salt — two  or  three  parts  of  bone 
meal  to  one  or  two  of  salt;  or  two-thirds  of  a  pound  of  cottonseed 
meal  and  four  ounces  of  bone  meal  per  head  each  day.  Calves  raised 
from  cows  receiving  bone  meal  were  in  better  condition  than  those 
from  the  control  animals.  Ten  calves  from  the  test  cows  at  200  days 
of  age  weighed  from  250  to  365  pounds  each,  while  seven  calves  from 
the  control  cows  at  the  same  age  weighed  235  to  300  pounds  each. 
From  the  results  of  the  work  Schmidt  concludes 
"That  feeding  bone  meal  and  salt  mixtures  as  here  used 

1.  Increases  the  gain  in  weight  during  the  favorable  season. 

2.  Cows  thus  fed  rear  better  calves. 

3.  Effectively  prevents  creeps. 

4.  Reduces  the  losses  from  diseases  other  than  those  of  an  infec- 
tious character. 

5.  Finely  ground  rock  phosphate  can  not  be  used  to  take  the  place 
of  bone  meal." 

In  certain  parts  of  Montana  bone  chewing  has  been  observed  for 
many  years  and  was  reported  upon  by  Welch. (33)  He  has  brought 
out  the  interesting  observation  that  before  ranges  were  fenced  cattle 
could  drift  during  grazing  over  very  wide  areas  and  thus  find  forage 
to  meet  their  requirements.  Cattlemen  had  ascertained  from  practical 
observation  that  some  areas  were  superior  to  others  and  that  certain 
ranges  were  not  at  all  suited  to  cattle  grazing.  With  the  confining  of 
cattle  under  fence  and  utilization  of  the  better  soil  areas  for  farming 
operations  it  was  quite  conceivable  that  cattle  could  be  limited  in 
their  movements  to  areas  where  the  forage  did  not  supply  all  the 
essential  substances  required  in  their  nutrition. 


BUL.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  21 

It  has  long  been  recognized  that  livestock  raised  in  certain  sections 
of  this  and  other  countries  were  of  uniform  high  quality.  The  blue 
grass  region  of  Kentucky  may  be  mentioned  as  such  an  area  in  the 
United  States. 

Great  variations  were  observed  by  Welch (33'  in  the  amount  of  salt 
required  on  different  ranches.  In  parts  of  the  Yellowstone,  cows 
were  observed  to  require  hardly  an  ounce  of  salt  per  month  while 
on  other  ranges  an  ounce  per  day  may  be  used  by  each  animal. 

In  the  affected  areas  in  Montana  the  bone  chewing  symptom  is 
confined  to  the  animals  on  the  native  grasses  or  hay.  They  may  be 
supplied  with  an  abundance  of  this  feed,  and  water,  and  yet  present 
the  picture  of  starvation.  On  only  a  few  ranches,  however,  was  the 
mineral  deficiency  so  great  as  to  cause  actual  death  of  the  cattle,  but 
poor  calves  and  the  general  unthriftiness  made  the  cattle  business 
unprofitable.  In  some  cases  where  the  pasture  vegetation  changed, 
particularly  by  developing  a  thin  stand  of  clover,  the  bone  chewing 
habit  disappeared.  Feeding  bone  meal  had  the  same  effect  and  no 
difficulty  was  experienced,  as  a  rule,  in  getting  the  animals  to  eat  the 
bone  meal  even  without  mixing  it  with  salt.  Affected  cattle  eat  a 
surprising  amount  when  it  is  first  supplied  but  this  soon  satisfies 
their  craving  and  the  amount  is  rapidly  reduced.  In  most  herds  there 
are  a  few  cattle  which,  once  having  acquired  the  habit,  will  retain  it 
more  or  less  permanently.  The  effectiveness  of  results  from  supplying 
bone  meal  in  those  areas  in  Montana  can  best  be  observed  over  a 
period  of  several  years  rather  than  of  a  few  weeks  or  months  or  even 
of  a  year.  This  brings  out  the  importance  of  a  continuous  supply  of 
bone  meal  in  such  areas. 

The  most  comprehensive  work  in  this  country  on  this  trouble  has 
been  carried  out  at  the  Minnesota  Station  by  Eckles,  Becker  and 
Palmer. (2)  A  mineral  deficiency  in  cattle  was  found  by  these  workers 
to  exist  in  32  counties  in  Minnesota.  In  a  survey  of  the  affected  areas 
many  farms  were  found  on  which  cows  were  expected  to  produce  a 
calf  only  once  in  two  years  and  heifers  sometimes  did  not  show  estrum 
until  two  years  of  age.  In  general  the  native  wild  hay  was  considered 
the  cause  of  the  trouble,  but  on  one  or  two  farms  feeding  of  home 
grown  alfalfa  hay  did  not  stop  the  appearance  of  the  condition.  In 
all  cases  where  bone  meal  was  fed  no  evidence  of  mineral  deficiency 
existed  except  on  two  farms  where  it  had  not  been  given  in  sufficient 
amounts.  The  deficiency  was  found  to  be  more  severe  after  short 
pasture  seasons  due  to  drought. 

Their  experimental  work  on  the  prevention  of  depraved  appetite 
through  feeding  bone  meal,  its  production  under  controlled  condi- 


22  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

tions,  and  curing  affected  animals  through  addition  of  single  mineral 
supplements,  all  tended  to  show  that  lack  of  phosphorus  was  the  chief 
causative  factor  in  the  trouble.  This  lack  also  involved  the  inhibition 
of  estrum.  The  possibility  of  low  intensity  of  ultra  violet  light  during 
the  winter  months  and  the  lack  of  a  factor  supplied  by  green  feed 
may  also  have  been  involved,  in  the  opinion  of  these  workers. 

In  a  later  publication,  Palmer  and  Eckles(19)  report  studies  made 
in  the  inorganic  calcium  and  phosphorus  in  the  blood  of  the  affected 
animals  and  found  further  proof  of  the  causes  of  the  trouble  outlined 
in  the  first  publication. 

The  blood  plasma  of  the  affected  animals  was  found  to  be  abnor- 
mally low  in  inorganic  phosphorus.  This  was  found  whether  calcium 
carbonate  was  given  as  a  supplement  to  the  deficient  ration  or  not. 
The  calcium  content  of  the  plasma  was  normal  in  all  cases.  The 
product  of  the  calcium  times  the  phosphorus  in  these  animals  was 
rarely  above  30  and  frequently  much  below  20.  In  marked  contrast 
to  this  was  the  normal  composition  of  the  blood  of  animals  fed  the 
deficient  ration  to  which  was  added  NaH2  P04  (sodium  dihydrogen 
phosphate).  In  these  cases  the  calcium  times  the  phosphorus  ranged 
from  50  to  75.  The  work  of  Kramer  and  Howland(15)  has  shown  that 
rickets  is  to  be  suspected  in  children  when  the  product  of  the  calcium 
and  phosphorus  is  below  30  and  its  existence  is  still  probable  when 
this  is  between  30  and  40. 

In  1926  a  report  of  a  similar  trouble  in  several  counties  in  Wis- 
consin was  made  by  Hart,  Beach,  Delwiche,  and  Bailey. (8>  In  the 
affected  areas  the  trouble  appeared  in  cattle  on  sweet  clover  pastures 
and  in  those  being  fed  alfalfa  hay  in  abundance,  thus  pointing  to  a 
phosphorus,  rather  than  a  lime  deficiency. 

By  placing  6  animals  from  various  affected  herds  on  rations  liberal 
in  phosphorus  for  a  period  of  3  months  a  remarkable  improvement 
was  noticed.  Each  of  the  animals  gained  over  200  pounds,  and  one 
322  pounds ;  the  stiffness  disappeared,  hides  became  loose  and  supple, 
and  milk  production  increased  50  per  cent.  The  addition  of  cod  liver 
oil  added  to  make  sure  that  there  was  abundance  of  vitamin  D,  which 
animals  need  to  enable  them  to  utilize  calcium  and  phosphorus  in  the 
feed,  did  not  seem  to  improve  the  ration.  They  suggest  that  better 
feeding  will  protect  against  this  disease  and  recommend  adding  20  to 
25  per  cent  of  wheat  bran,  which  is  rich  in  phosphorus,  to  the  grain 
mixture.  This  would  be  impractical  in  range  herds  and  the  same 
result  could  probably  be  accomplished  by  the  feeding  of  bone  meal. 

Elliott,  Orr  and  Wood(3)  in  Part  II  of  their  investigation  on 
mineral  content  of  pasture  grass  on  the  British  Isles  state : 


BUL.  458]  PERCENTAGE   OF    CALF   CROP   IN   RANGE   HERDS  23 

"1.  The  results  of  previous  investigations  showing  that  there  is 
no  striking  difference  in  the  energy  value  between  good  and  poor 
pasture  are  fully  confirmed. 

2.  Wide  differences,  however,  do  exist  in  the  proportions  in  which 
the  mineral  constituents  are  present  in  different  pastures. 

3.  These  differences  correspond  closely  with  the  respective  value 
to  the  stockman  of  the  pasture  in  which  they  occur,  a  high  mineral 
content  being  associated  with  high  nutritive  value.' ' 

In  general,  they  found  that  the  forage  in  the  so-called  fattening 
pastures  was  higher  in  mineral  content  and  protein  than  in  the  non- 
fattening  pastures.  They  also  found  that  the  ash  content  of  eaten 
grasses  was  higher  than  in  that  which  was  not  eaten.  In  this  connec- 
tion, sheep  having  free  choice  in  grazing  showed  a  preference  for 
herbage  containing  a  higher  percentage  of  mineral  ingredients. 

J.  S.  McHargue(16)  of  the  Kentucky  Station,  has  suggested  the 
possible  important  functions  in  the  plant's  economy  of  certain  ele- 
ments, found  in  very  small  quantities  in  plants,  such  as  manganese, 
copper,  zinc,  nickel,  cobalt,  barium,  strontium,  boron,  arsenic,  fluorine 
and  bromine.  In  carefully  controlled  experiments  it  has  been  shown 
that  plants  in  sand  cultures  containing  the  so-called  ten  essential 
elements  will  not  grow  after  the  food  material  of  the  plant  seeds  has 
been  utilized.  Under  such  conditions  the  addition  of  a  small  amount 
of  a  manganese  compound  increases  the  growth  and  a  small  amount 
of  copper  then  added  makes  the  plant  still  larger  and  more  nearly 
normal.  He  states,  "Marine  and  fresh-water  mollusks  are  quite  rich 
in  manganese,  copper  and  zinc.  Birds  apparently  contain  more  man- 
ganese than  some  of  the  higher  type  of  domestic  quadrupeds.  How- 
ever, appreciable  amounts  of  manganese,  copper,  zinc  and  boron  are 
normal  constituents  of  the  tissues  of  domestic  animals.  These  ele- 
ments have  been  found  in  greater  concentration  in  the  embryo  of  such 
animals  as  have  been  examined,  than  in  the  tissues  of  mature  animals 
of  the  same  species.  The  liver,  kidneys,  spleen,  pancreas,  heart  and 
brain  contain  more  of  these  elements  than  the  lean  muscular  tissues 
or  the  blood.  However,  their  presence  can  be  detected  in  the  latter. 
The  bluegrass  region  of  central  Kentucky  is  underlain  with  phos- 
phatic  limestones  which,  upon  disintegration,  produce  a  soil  relatively 
rich  in  manganese,  copper,  zinc,  nickel  and  cobalt,  and  the  presence 
of  these  elements  can  be  detected  in  the  forage  crops  produced.  It  is 
therefore  assumed  that  the  presence  of  these  elements  in  the  herbage 
produced  in  this  region  is  a  contributing  factor  in  the  development  of 
the  superior  specimens  of  livestock  for  which  the  country  has  long 
since  attained  a  world-wide  fame." 


24  UNIVERSITY   OF   CALIFORNIA — EXPERIMENT   STATION 

These  statements  are  particulary  significant  in  the  light  of  the 
very  recent  findings  of  Hart,  Steenbock,  Elvehjen  and  Waddell(9) 
on  the  importance  of  copper  as  an  essential  factor  in  the  diet  of  mam- 
malia to  prevent  anemia.  A  shortage  of  iron  has  always  been  consid- 
ered the  cause  of  this  condition  and  while  their  work  shows  it  to  be 
still  the  limiting  factor  the  effectiveness  of  its  administration  depends 
on  the  presence  of  copper. 

The  recent  wide  use  of  liver  as  a  cure  for  anemia  apparently  thus 
depends  on  the  presence  of  minute  amounts  of  copper.  In  ashing 
liver  they  found  a  pale  bluish  color  which  suggested  the  presence  of 
copper.  Rats  showing  marked  anemia  from  a  pure  milk  diet  were 
strikingly  cured  when  copper  sulphate  was  added  as  a  supplement 
to  pure  ferric  chloride. 

The  herd  of  purebred  beef  cattle  at  the  University  Farm  is  kept 
under  rather  ideal  conditions  and  on  a  high  plane  of  nutrition.  They 
get  alfalfa  and  sudan  grass  pasture  during  the  long  summer  and 
autumn  seasons.  In  the  winter,  which  is  relatively  short,  they  get 
alfalfa  hay  and  corn  silage.  In  the  spring  they  are  turned  into  a 
native  grass  pasture  containing  a  variety  of  forage  plants.  It  can 
thus  be  seen  that  a  high  percentage  calf  crop  should  be  expected  and 
such  has  been  the  case.  The  herd  has  consisted  of  about  41  head  of 
females  of  breeding  age  representing  the  Aberdeen- Angus,  Shorthorn 
and  Hereford  breeds.  During  the  period  from  January  1,  1923,  to 
January  1,  1928,  a  total  of  206  cows  were  bred  and  183  became  preg- 
nant, or  88.83  per  cent.  In  this  period  occurred  an  abortion  infection 
causing  19  abortions  and  several  of  these  cows  failed  to  breed  the 
following  year.  Three  calves  died  at  birth  from  mechanical  abnor- 
malities, and  two  cows  were  killed  during  pregnancy.  This  left  159 
calves  weaned  or  77  per  cent.  There  have  been  several  females  in  this 
group  15  years  old  or  more  kept  to  get  additional  offspring  from 
them.  The  important  observation  in  this  herd  is  that  a  high  plane  of 
nutrition  under  these  conditions  favors  rather  than  militates  against 
a  high  percentage  of  calf  crop. 


BUL.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  25 


EVIDENCE  THAT  CATTLE  ON   CALIFORNIA   RANGES   MAY   BE   ON   A 
LOW   MINERAL  INTAKE   DURING   PARTS  OF  THE  YEAR 

The  foregoing  discussion  covers  such  serious  shortage  in  the  intake 
of  minerals  with  the  food  that  abnormalities  are  produced  in  the 
animals  pronounced  enough  to  be  definitely  classed  as  disease.  It 
must  be  recognized,  however,  that  variations  from  the  optimum  in 
mineral  nutrition  may  vary  greatly  in  degree.  The  results  may  be 
such  slight  changes  from  the  normal  that  they  can  not  be  recog- 
nized by  the  closest  observation  of  the  animal.  On  the  other  hand, 
they  may  be  so  marked  ,r.s  to  produce  alterations  in  the  physiological 
processes,  even  resulting  in  death.  Early  changes  are  noticed  in  alter- 
ation in  the  digestive  tract.  Thus  Orr{17)  in  experiments  on  pigs  with 
feeding  stuffs  poor  in  calcium,  noticed  the  development  of  convulsive 
seizures  and  frequently  gastro-intestinal  disorders. 

It  has  been  shown  that  on  diets  practically  lacking  in  minerals 
the  experimental  animals  died  sooner  than  when  no  food  was  given. 

In  a  discussion  of  the  importance  of  mineral  matter  in  nutrition 
Orr(18)  brings  out  the  fact  that  minerals  are  important  in  regulating 
the  interchange  of  fluids  between  the  lumen  of  the  intestinal  tract 
and  the  blood.  In  the  stomach  the  contents  must  be  acid  to  allow 
the  pepsin  of  the  gastric  juice  to  act  properly.  Increased  acid  in  the 
upper  part  of  the  small  intestine  stimulates  the  flow  of  digestive 
juices  from  the  pancreas.  Increased  mineral  salts  tend  to  cause  a  flow 
of  fluid  from  the  blood  to  the  intestines.  This  is  the  manner  in  which 
salts  act  as  a  laxative.  Low  mineral  intake  with  food  is  also  mani- 
fested by  reduced  appetite.  It  is  a  common  observation  on  our  cattle 
ranges  during  the  dry  feed  season  to  note  the  dry  and  comparatively 
hard  condition  of  the  feces  of  the  cattle.  This  tends  to  increase  as 
the  feed  becomes  poor  until  the  feces  are  evacuated  in  balls,  and  it 
is  generally  known  that  cattle  are  not  doing  well  when  their  feces  are 
in  this  condition.  There  is  evidence  that  the  mineral  content  of  the 
feed  is  responsible  for  this  condition.  Mild  bone  eating  has  been 
observed  in  several  counties  in  this  state. 


26  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 


STUDIES  ON    RANGE   GRASS   IN   CALIFORNIA 

In  February,  1927,  the  operator  of  a  large  ranch  in  Merced 
County,  California,  communicated  with  the  authors  in  regard  to  his 
observation  of  cattle  chewing  bones  in  that  section.  He  also  stated 
that  two  cows  with  calves  at  side  were  given  bone  meal.  These  cows 
ate  from  1  to  2  pounds  of  bone  meal  each  per  day  for  a  period  of  two 
weeks  and  for  a  considerably  longer  period  a  similar  amount  every 
two  days.  Daily  consumption  then  gradually  decreased.  The  bone 
meal  was  of  low  grade,  coarsely  ground  and  had  a  decidedly  bad  odor. 
The  fact  that  these  animals  ate  such  quantities  indicated  a  decided 
deficiency.  The  bone  meal  was  probably  poorly  utilized  on  account 
of  its  coarseness.  Until  the  time  of  the  first  communication  the  cattle 
had  subsisted  upon  the  dry  feed  of  the  previous  year.  Some  young 
green  forage  was  available  in  February. 

The  ranch  is  east  of  the  San  Joaquin  River,  comprising  low  land, 
and  the  general  topography  is  level.  It  is  typical  of  so-called  "hog 
wallow"  lands  of  which  there  is  a  considerable  area.  On  this  type  of 
range  there  are  alternate  knolls  and  depressions,  the  areas  of  which 
are  commonly  not  over  a  few  square  rods  in  size.  White  alkali  is 
apparent  in  many  of  the  swales.  The  knolls  grow  a  luxuriant  vegeta- 
tion when  there  is  sufficient  rainfall.  The  vegetative  growth  in  the 
low  portions  is  stunted,  seldom  attaining  a  height  of  more  than  4  to 
6  inches.    Cattle  graze  almost  entirely  upon  the  knolls. 

The  forage  consists  of  bur  clover  (Medicago  Imp  Ida),  foxtail 
(Hordeum  mwrinum),  wild  oats  (Avena  barbata),  soft  chess  or  cheat 
(Bromus  hordeaceus),  needle  brome  (Bromus  rigidus),  salt  grass 
(Distichlis  spicata)  and  other  species  of  minor  importance.  The  first 
four  are  most  important.  The  amount  of  bur  clover  varies  from 
season  to  season,  sometimes  being  abundant  and  at  other  times  rela- 
tively scant. 

A  herd  of  225  head  of  cows  was  purchased  in  Texas  in  the  fall  of 
1925  and  brought  to  this  ranch.  The  owner  stated  that  they  dropped 
204  calves  in  the  spring  of  1926.  They  were  rebred  and  from  this 
same  herd  68  calves  were  produced  in  the  spring  of  1927.  It  was  the 
operator's  opinion  that  it  was  a  common  experience  for  the  percent- 
age calf  crop  to  drop  after  the  females  had  been  on  this  type  of  range 
for  a  year. 

Two  other  herds  of  cattle  were  brought  to  the  ranch  in  the  fall 
of  1926,  one  a  purebred  herd  of  155  head  and  the  other  a  grade  herd 


BUL.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  27 

of  100  head.  Bone  meal  was  plaeed  in  troughs  in  the  pasture  occu- 
pied by  the  purebred  herd  beginning  about  May  1,  1927.  The  feed 
was  excellent  at  this  time,  but  the  cattle  ate  some  bone  meal.  During 
the  period  from  May  to  October  they  consumed  about  600  pounds  of 
bone  meal.  This  is  not  an  accurate  measure  of  their  appetite  as  the 
troughs  were  empty  a  considerable  part  of  the  time.  The  rate  of 
consumption  increased  when  the  feed  dried.  Two  hundred  pounds 
of  bone  meal  were  placed  in  the  troughs  the  first  of  July  and  were 
consumed  within  a  few  days.  The  cattle  remained  in  excellent  condi- 
tion throughout  the  season  due  largely  to  an  excellent  crop  of  bur 
clover  which  makes  very  nutritious  dry  feed. 

In  1927  these  two  herds  weaned  71.6  per  cent  and  84.5  per  cent 
calf  crop,  respectively.  In  October  when  the  calves  were  weaned  the 
owner  supplied  bone  meal  to  both  groups.  They  have  now  dropped 
their  1928  calf  crop.  The  purebred  herd  produced  an  86  per  cent 
crop  while  the  grade  herd  produced  88  per  cent.  Feed  conditions 
were  such  this  particular  year  that  no  advantage  was  obtained  from 
feeding  bone  meal  as  it  was  supplied  during  the  breeding  season  of 
1927. 

The  seasonal  sequence  of  grazing  was  roughly  as  follows : 

During  the  early  vegetative  stages  the  cattle  ate  some  of  the  dry 
roughage  along  with  the  new  growth.  When  the  new  forage  became 
plentiful  the  cattle  grazed  largely  upon  the  foxtail  which  is  among 
the  earliest  grasses.  Later  the  other  species  of  grasses  were  included 
and  also  bur  clover  to  a  small  extent.  Cattle  do  not  graze  bur  clover 
extensively  in  the  green  stages  where  other  feed  is  plentiful,  due 
probably  to  its  somewhat  bitter  taste. 

The  bur  clover,  foxtail  and  brome  grasses  dried  at  about  the  same 
time  in  the  early  part  of  May.  The  wild  oats  headed  out  during  this 
month  and  at  the  last  of  the  month  still  retained  some  green  color. 
At  this  time  the  cattle  were  grazing  the  wild  oats  and  the  dried  bur 
clover.  At  about  this  time  the  salt  grass  appeared.  During  the 
remainder  of  the  season  the  cattle  grazed  the  bur  clover  patches, 
getting  stems,  leaves  and  burs,  together  with  some  stems  of  dry 
grasses.  They  also  took  some  of  the  salt  grass.  This  grass  retains 
some  green  color  throughout  the  season.  The  bur  clover  supply  was 
rather  meager  by  October.  Rains  came  early  and  by  December  the 
new  feed  was  excellent,  thus  the  season  during  which  the  cattle  had 
to  rely  on  inferior  feed  was  rather  short  during  this  particular  year. 
Frequently,  however,  under  a  similar  rate  of  stocking  the  bur  clover 
supply  would  be  exhausted  much  earlier  in  the  season  and  often  rains 


28 


UNIVERSITY   OF    CALIFORNIA — EXPERIMENT    STATION 


come  late  and  new  growth  is  meager  due  to  cold  weather  with  the 
result  that  good  new  feed  is  not  obtained  until  February  or  March. 
Forage  samples  were  collected  from  time  to  time  throughout  the 
season  and  submitted  to  chemical  analysis  for  calcium  and  phosphorus 
and  in  some  cases  other  constituents  of  the  ash.  The  data  secured  are 
shown  in  table  3. 

TABLE  3 

Ash  Analyses  of  Eange  Forage  from  Merced  County 
(All  figures  are  in  percentage  on  the  dry  basis.) 


Date 

Condition  . 

Total 
ash 

CaO 

P2O5 

Si 

MgO 

Na20 
1.18 

K20 

2.78 

CI 
0.51 

Fe 

t 

3/28/27 
*3/30/27 
5/31/27 
7/14/27t 
7/ 14/27* 
10/3/27 

10.06 
10.42 
9.45 
16.05 
13.03 
17.61 

1.28 
1.27 
1.36 
1.15 
1.45 
1.54 

0.86 
1.09 
0.55 
0.43 
0.49 
0.60 

0.28 

0  56 

0.012 

Dry 

2.17 

0.99 

0.42 

1.68 

0.47 

0.119 

Dry 

Dry 

Dry 

8.95 

( 

5/31/27 

10/3/27 

Dry 

5.91 
9.26 

1.13 
1.06 

0.83 
0.85 

Dry 

1 

c 

3/28/27 

5/31/27 

10/3/27 

12/20/27 

9.97 
14  31 
12.42 

0.43 
0.30 
0.32 
0.52 

0.83 
0.29 
0.30 
0.97 

3.37 
9.41 
8.52 

0.28 
0.19 

0.94 
0.89 

2.54 
1.32 

1.02 
2.06 

0.013 

Dry 

0.022 

Foxtail < 

Dry 

Green  (6-8  in.  high) 

v 

5/31/27 

Dry 

9.10 

0.43 

0.25 

4.63 

0.32 

0.40 

1.43 

1.00 

0.013 

t 

5/31/27 
7/14/27 
10/3/27 

10  07 

16.44 
28.68 

0.35 
0.32 
0.39 

0.39 
0.30 
0.23 

5.74 

0.38 

0.64 

1.30 

2.02 

0.042 

11.95 

^ 

5/31/27 

9.10 

0.21 

0.28 

6.05 

0.15 

0.67 

1.05 

0.95 

0.022 

Composite  sample  \ 
(knolls)                  \ 

3/24/27 

4/22/27 

8.88 
8.24 

0.66 
0.60 

0.82 
0.52 

3.02 

0.36 

0.011 

Composite  samplef 

3/24/27 
4/22/27 

11.78 
9.85 

0.59 
0.51 

0.97 
0.80 

1.41 

0.42 

0.010 

*  Sample  from  University  Farm. 

t  Collected  where  cattle  were  grazing.   Sample  contained  some  stems  of  grass  plants. 

%  Collected  outside  of  the  pasture  and  was  fairly  representative  of  entire  plant. 

The  foxtail,  brome  grasses,  wild  oats  and  salt  grass  were  all  rela- 
tively low  in  calcium  even  in  the  succulent  stages.  A  decline  is  noted 
in  the  calcium  oxide  content  of  the  foxtail  from  .52  per  cent  in  the 
early  vegetative  stage  to  .30  per  cent  in  the  dry  forage.  Wild  oats 
showed  the  lowest  calcium  oxide  content  of  any  of  the  grasses,  namely, 
.21  per  cent  in  the  partly  dried  plants.  The  calcium  content  of  the 
bur  clover  remained  high  throughout  the  season. 


BUL.  458]  PERCENTAGE   OF    CALF   CROP   IN   RANGE   HERDS  29 

The  phosphorus  content  of  the  grasses  decreased  rapidly  as  the 
plants  approached  maturity  and  dried.  The  vegetative  part  of  the 
bur  clover  apparently  decreased  in  phosphorus,  but  as  would  be 
expected  the  burs  containing  the  seeds,  retained  a  high  calcium  and 
phosphorus  content  throughout  the  season.  During  the  late  summer 
months  it  was  difficult  to  obtain  samples  of  bur  clover  which  had  an 
amount  of  leaves,  stems  and  burs  representative  of  the  entire  plant 
earlier  in  the  season.  Sample  No.  1  collected  July  14  was  taken  where 
animals  were  grazing  and  seemed  fairly  representative  of  the  material 
as  eaten.  It  probably  contained  a  lower  proportion  of  burs  than 
sample  No.  2  which  was  collected  outside  the  pasture  and  contained 
leaves,  stems  and  burs  fairly  representative  of  the  entire  plant.  There 
were  also  stems  of  grass  plants  included  in  sample  No.  1  which 
accounts  to  some  extent  for  the  lower  P205  content. 

Later  in  the  season  considerable  dust  was  on  the  plants  and  was 
the  cause  of  the  decided  increase  in  silica  content.  This  is  especially 
true  of  the  last  sample  of  bur  clover  and  of  salt  grass,  the  latter  hav- 
ing a  sticky  exudate  thus  collecting  large  quantities  of  dirt. 

These  data  show  that,  aside  from  bur  clover,  the  dried  roughage 
contained  an  amount  of  calcium  and  phosphorus  which  is  below  that 
required  for  optimum  nutrition.  If  the  bur  clover  crop  is  meager 
and  the  cattle  have  to  rely  upon  the  dried  grasses  throughout  most 
of  the  summer  while  still  suckling  calves,  it  seems  probable  that 
breeding  efficiency  would  be  interfered  with  resulting  in  low  calf 
crop  the  following  year.  These  dried  grasses  are  also  low  in  protein 
and  can  not  be  expected  to  furnish  much  above  body  maintenance 
requirements  for  energy. 

A  digestion  trial  by  Mead  and  Guilbert  of  this  station,  data  not 
yet  published,  with  dried  range  grass  from  Mendocino  County,  col- 
lected by  A.  W.  Sampson  of  the  Division  of  Forestry,  showed  little 
or  no  digestible  protein,  43.4  pounds  digestible  carbohydrate  and  .47 
pounds  of  digestible  fat  in  100  pounds  of  the  material.  This  forage 
contained  .28  per  cent  calcium  oxide  and  .38  per  cent  phosphoric 
acid.  It  contained  about  60  per  cent  soft  chess  or  cheat,  the  remain- 
ing 40  per  cent  consisting  of  needle  brome,  wild  oats,  foxtail  and 
other  species.  A  sample  of  the  same  forage  cut  earlier  after  the  seed 
heads  had  formed  and  while  still  retaining  the  green  color,  contained 
.34  per  cent  calcium  oxide  and  .79  per  cent  phosphoric  acid,  indi- 
cating further  the  rapid  decrease  of  phosphorus  which  takes  place  as 
the  plants  mature  and  dry. 

The  P205  content  of  the  grasses  from  the  Merced  range  is  some- 
what higher  than  that  reported  by  Theiler  et  al(28)  in  South  Africa 


30  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

which  varied  from  .60  per  cent  in  the  early  green  stages  to  .09  per 
cent  in  the  old  dry  grass.  The  dry  grass  is  only  slightly  higher  in 
phosphorus  than  the  prairie  hay  and  timothy  hay  from  affected  areas 
in  Minnesota,  as  reported  by  Eckles,  Becker  and  Palmer(2)  where  a 
phosphorus  deficiency  was  clearly  demonstrated. 

The  calcium  oxide  content  is  very  similar  to  that  of  the  forage 
in  the  Falkland  Islands,  as  reported  by  Elliott,  Orr  and  Wood(4) 
where  a  deficiency  in  the  calcium  wTas  considered  the  limiting  factor, 
as  the  P205  content  of  the  grass  was  .54  per  cent.  The  soil  in  the 
Falkland  Islands  is  deficient  in  calcium  and  this  deficiency  limits  not 
only  calcium  but  other  ash  ingredients  in  the  plants.  The  P205  con- 
tent of  grass  was  increased  markedly  by  liming  the  soil. 

The  Na20  (sodium  oxide)  content  of  the  Merced  grasses  varied 
from  .40  per  cent  to  1.18  per  cent  while  the  chlorine  varied  from  .47 
per  cent  in  bur  clover  to  2.06  per  cent  in  salt  grass.  The  sodium  con- 
tent is  much  higher  than  reported  for  pasture  grasses  in  England  and 
Wales  by  Elliott,  Orr  and  Wood(4)  and  the  chlorine  content  is  high 
especially  in  the  salt  grass.  This  grass  is  decidedly  salty  to  the  taste, 
especially  late  in  the  season.  Cattle  on  this  range  eat  very  little  salt. 
Apparently  they  secure  an  adequate  supply  from  the  forage.  The 
ratio  of  sodium  to  potassium  is  relatively  narrow  which  would  also 
tend  to  diminish  the  salt  requirement. 

The  iron  content  appears  to  be  sufficient,  so  that  there  is  no  reason 
to  believe  that  iron  deficiency  is  concerned.  There  does  not  appear 
to  be  anything  unusual  in  the  magnesium  content  of  the  forage. 

Theiler(28)  et  al  computed  roughly  the  minimum  requirement 
for  P205  below  which  osteophagia  appeared,  by  assuming  8  pounds 
of  "starch  equivalent"  to  be  the  ordinary  energy  requirement  for  a 
1000  pound  grazing  animal,  not  counting  growth  or  milk  production. 
The  energy  intake  was  considered  the  limiting  factor  in  amount  of 
forage  consumed.  He  computed  the  starch  value  of  the  forage  at 
different  seasons  and  determined  roughly  the  total  food  and  total 
P20-  intake  daily.  By  this  means  he  shows  a  P205  intake  of  38  grams 
daily  during  the  season  of  highest  intake  when  the  grass  was  in  the 
early  vegetative  stages.  From  this  time  the  amount  ingested  rapidly 
declined  to  11  grams  daily  on  the  old  dry  grass.  By  comparing  the 
records  of  the  percentage  of  osteophagia  in  the  cattle  he  arrived  at  an 
intake  of  27  grams  daily  as  the  amount  below  which  the  incidence  of 
osteophagia  is  high. 

The  estimated  starch  value  of  the  Merced  range  grass  is  28  pounds 
per  hundred  weight  of  the  material.  A  thirty  pound  daily  intake 
for  a  1000  pound  animal  would  yield  slightly  over  8  pounds  of  "starch 


BUL.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  31 

equivalent."  This  amount  of  dry  matter  is  close  to  the  maximum 
which  can  be  handled  by  a  1000  pound  animal  and  probably  in  excess 
of  what  it  is  able  to  obtain  on  the  range. 

The  average  P205  content  of  the  dry  grass  from  June  on  to  the 
time  of  new  growth  was  about  .28  per  cent.  Thirty  pounds  would 
supply  .084  pounds  or  38.1  grams  of  P205  or  an  amount  above  that 
found  by  Theiler  as  required  to  prevent  decided  osteophagia.  This 
together  with  the  fact  that  the  phosphorus  content  of  the  grass  is 
relatively  high  during  a  longer  season  of  the  year,  even  if  bur  clover 
is  absent,  probably  accounts  for  the  relatively  small  amount  of  bone 
chewing  noted  by  cattlemen  in  this  district. 

The  South  African  studies  have  shown,  however,  that  a  nutri- 
tional deficiency  exists  on  an  intake  above  that  where  osteophagia  is 
evident.  This  is  manifested  by  stunted  growth  and  low  milk  yields 
which  are  quickly  improved  by  bone  meal  feeding.  Hart,  Steenbock 
and  Humphrey (10)  in  their  study  of  the  influence  of  a  ration, 
restricted  to  the  oat  plant,  upon  reproduction  in  cattle,  concluded  that 
the  principal  deficiency  was  in  calcium  and  that  the  ration  of  herbivo- 
rous animals  should  contain  at  least  .45  per  cent  CaO  for  high 
reproductive  efficiency. 

It  seems  clear  from  the  above  discussion  that  the  dry  range  grass 
is  deficient  both  in  calcium  and  phosphorus  and,  in  addition,  the 
conditions  for  their  assimilation  are  probably  not  favorable.  The 
work  of  Hart,  Steenbock,  Scott  and  Humphrey (11)  casts  some  doubt 
as  to  whether  cattle  are  favorably  affected  in  regard  to  mineral  meta- 
bolism by  direct  sunlight,  and  the  general  appearance  of  the  forage 
would  certainly  not  suggest  high  vitamin  D  potency. 

POSSIBLE   DEFICIENCIES  IN  OTHER  AREAS 

A  form  of  osteomalacia  occurring  chiefly  in  dairy  calves  has  been 
found  in  Kings  County  at  irregular  intervals  and  was  reported  upon 
with  illustrations  by  Haring(7)  in  1922.     (See  figures  1.  2  and  3.) 

On  one  ranch  in  a  single  year  15  out  of  18  calves  had  broken 
bones  and  had  to  be  killed.  Only  one  milk  cow  out  of  27  became 
affected  and  she  recovered.  The  calves  became  affected  even  while 
being  pastured  on  apparently  good  alfalfa  pasture.  When  they  were 
removed  at  weaning  time  to  another  field  only  one  mile  away  they 
did  not  develop  the  trouble. 

No  phosphorus  determinations  were  made  on  the  samples  of  feed 
taken  from  the  pasture.  Samples  of  hay  containing  alfalfa  and  other 
grasses  showed  a  P205  content  varying  from  0.40  to  0.53  and  their 


32 


UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 


.JMZi 


Fig.  1. — Side  view  of  a  case  of  osteomalacia  in  Kings  County,  May,  1921. 

(After   Haring.) 


iste 


Fig.  2. — Front  view  of  same  case  as  shown  in  figure  1.    (After  Haring.) 


BUL.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  33 

CaO  (calcium  oxide)  content  was  high,  varying  from  1.54  to  2.21. 
One  analysis  of  salt  grass  in  the  alfalfa  hay  that  was  separated  and 
tested  alone  showed  a  P2O0  content  of  0.09  and  CaO  content  of  0.27. 
It  was  also  stated  that  in  some  cases  osteomalacia  developed  in  animals 
fed  on  hay  consisting  of  salt  grass  and  foxtail,  and  that  these  animals 
recovered  when  fed  from  a  stack  of  alfalfa  hay. 

In  the  winter  of  1917  and  1918,  rains  came  very  late  and  green 
feed  was  not  available  until  February  in  parts  of  the  state.  In  Jan- 
uary a  peculiar  lameness  of  dairy  cows  developed  along  the  coast 
north  of  Santa  Cruz.  This  condition  occurred  on  the  ranches  feeding 
red  oat  hay.  In  the  center  of  the  area  one  ranch  raised  and  fed  alfalfa 
hay  and  no  cases  occurred  on  this  place. 

Some  of  the  animals  were  so  badly  affected  that  they  would  stand 
and  try  to  move  around,  resting  the  weight  of  the  front  part  of  their 
bodies  on  the  knees.  With  the  growth  of  green  feed  the  trouble, 
disappeared  and  since  that  time  pasture  has  always  been  available 
much  earlier  and  no  cases  have  been  reported. 

At  the  time,  one  of  the  worst  affected  cases  was  killed  and  a  post- 
mortem examination  made  including  sectioning  of  the  phalanges  of 
the  front  legs.  No  definite  conclusions  were  reached  at  the  time 
regarding  the  trouble,  but  it  was  considered  to  be  due  to  nutritional 
causes. 

An  inquiry  from  a  cattleman  regarding  the  supplementary  feeding 
of  beef  cattle  in  San  Bernardino  County  contained  the  statement 
that  his  cows  failed  to  come  in  heat  on  his  pastures  while  suckling 
calves  and  thus  failed  to  have  a  calf  each  year.  This  man  also  stated 
that  he  had  overcome  the  difficulty  by  feeding  chopped  citron  and 
wheat  bran.  Wheat  bran  is  especially  rich  in  phosphorus,  furnishes 
a  fair  amount  of  protein  and  is  probably  largely  responsible  for  the 
good  results  obtained. 

Occasional  cases  of  bone  chewing  have  been  reported  in  certain 
sections  of  the  Sierra  foothills.  In  much  of  this  country  the  range 
forage  consists  largely  of  the  grass  species  along  with  a  varying 
amount  of  alfilaria.  The  alfilaria  is  good  early  feed  and  the  grass 
species  are  fairly  nutritious  in  the  green  stages.  On  this  type  of 
range,  cattlemen  depend  generally  upon  high  mountain  range  for 
summer  forage  and  come  back  to  the  lower  range  in  the  fall.  Fre- 
quently the  cattle  must  subsist  for  a  considerable  length  of  time 
upon  the  old  forage  on  the  lower  range  before  new  feed  is  available. 
Meager  data  are  as  yet  available  upon  the  nutritive  value  of  the 
forage  on  the  high  mountain  ranges.    It  is,  however,  common  expe- 


34  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 


Fig.  3. — Fractured  humeri  of  ITolstein  heifer  bom  in  the  spring  of  1921  in 
Kings  County.  Pastured  on  alfalfa,  developed  symptoms  in  November,  was  moved 
one  mile  away  and  improved.  Was  returned  in  January,  quickly  relapsed  and 
broken  legs  necessitated  slaughter  .January  25,  1922.    (After  Haring.) 


BUL.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  35 

rience  for  cows  suckling  calves  to  come  out  in  thin  condition  in  the 
fall.  The  logical  time  for  the  breeding  cow  to  replace  nutrition 
reserves  lost  in  calving  and  during  the  suckling  period  is  in  the  fall 
after  weaning  time.  Since  a  large  percentage  of  the  weight  of  the 
unborn  calf  is  also  produced  during  the  last  few  months  of  pregnancy, 
breeding  cows  should  be  gaining  at  this  time.  Failure  to  gain  in  this 
period  means  that  the  increase  in  the  weight  of  the  fetus  is  obtained 
at  the  expense  of  the  tissues  of  the  mother.  If  the  cow  is  already  thin, 
the  results  are  weak  condition  at  calving  time,  difficult  parturition,  a 
weak  calf  and  a  poor  milk  supply.  Even  on  good  spring  feed  the  cow 
may  not  get  in  condition  to  breed  and  thus  may  miss  calving  one 
season  in  order  to  get  back  to  an  adequate  plane  of  nutrition. 

When  cows  must  depend  upon  the  old  feed  of  the  grass  type  very 
little  if  any  gain  in  weight  can  be  expected,  and  frequently  they  will 
lose  weight.  Under  these  conditions  it  probably  is  not  possible  to 
make  replacement  of  mineral  reserves.  It  is  recognized  that  nutri- 
tional deficiency  resulting  in  thin  condition  and  impaired  reproductive 
function  may  be  due  to  the  inability  to  secure  an  adequate  quantity 
of  feed  in  a  day's  grazing  as  well  as  to  specific  deficiencies  in  the 
quality  of  the  feed.  In  other  words,  a  limited  amount  of  fair  quality 
feed  may  have  the  same  effect  as  a  feed  which  is  definitely  deficient 
in  one  or  more  nutrients.  Frequently  the  conditions  which  produce 
a  low  quantity  of  forage  will  also  produce  poor  quality. 

Adjusting  the  rate  of  stocking  of  ranges  to  avoid  serious  feed 
shortage,  even  in  the  poor  years,  is  of  utmost  importance  from  the 
standpoint  of  efficient  production  and  reproduction  in  the  cattle  and 
the  maintenance  and  improvement  of  the  range. 

Since  it  is  in  the  fall  that  the  poorest  quality  of  feed  is  available 
and  since  this  is  a  critical  period  for  both  the  cow  and  the  unborn 
calf,  it  is  important  to  improve  the  conditions  by  supplemental 
feeding  as  much  as  it  is  economically  possible  to  do  so. 

Table  4  shows  the  changes  in  the  organic  constituents  and  calcium 
and  phosphorus  in  range  grasses  at  different  seasons  of  the  year. 

Sample  No.  1  was  a  mixture  of  range  grasses  from  Mendocino 
County.  It  was  taken  from  forage  which  was  cut  in  the  fairly  mature 
but  green  state  and  made  into  hay.  The  second  sample  was  collected 
from  the  range  in  August.  The  chief  difference  in  these  two  forages 
is  in  the  protein  and  phosphorus  content.  These  data  show  the  possi- 
bility of  furnishing  a  feed  of  much  higher  value  for  the  cattle  when 
they  come  out  of  the  high  mountain  ranges  in  the  fall,  by  simply 
cutting  and  raking  the  forage  into  piles  or  windrows  before  it  matures 
and  dries. 


36 


UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 


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BUL.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  37 

In  the  next  group  of  analyses,  on  foxtail,  sample  No.  3  cut  in  the 
early  stage  was  high  in  protein,  low  in  fiber  and  high  in  phosphorus. 
The  amount  of  protein  is  approximately  3V2  times  as  great  as  in  sam- 
ples 4  and  5,  cut  when  fully  mature  and  dry.  A  similar  drop  is  found 
in  the  phosphorus.  The  fat  decreases  and  the  fiber  increases.  With 
this  increase  in  fiber  the  digestibility  rapidly  decreases.  The  most 
significant  difference  between  the  feed,  when  most  relished  by  live- 
stock and  when  it  is  clearly  recognized  as  poor  feed,  is  in  the  protein 
and  phosphorus  content.  The  change  from  a  succulent  to  a  dry 
fibrous  feed  of  course  markedly  affects  palatability  and  digestibility. 

The  same  trend  in  lower  protein  and  ash  content  is  found  in  the 
other  grasses.  It  should  be  noted  that  the  calcium  content  of  the 
grasses  from  Shingle  Springs  in  the  Sierra  Nevada  foothills  and  from 
Berkeley  is  higher  than  in  those  from  Merced  County.  The  phosphorus 
content  of  the  dry  grasses  was  also  higher  than  in  the  Merced  samples. 
The  calcium  content  of  foxtail  collected  at  Shingle  Springs,  for 
example,  is  about  60  per  cent  higher  than  that  found  at  any  time  in 
samples  from  the  Merced  range. 

The  third  group  of  analyses  on  bur  clover  from  the  Merced  County 
range  constituting  samples  7,  8  and  9,  show  a  high  protein  and  ash 
content  throughout  the  season,  and  indicate  the  reason  for  the  high 
value  placed  upon  this  feed  by  stockmen.  It  is  significant  to  again 
observe  that  the  most  striking  difference  in  the  chemical  composition 
of  this  good  feed  and  the  poor  feeds  is  in  the  protein  and  ash  constit- 
uents. The  lower  fiber  content  of  the  dry  bur  clover,  as  compared  to 
the  dry  grasses,  is  another  factor  in  its  favor,  but  this  difference  is 
not  nearly  so  great  as  in  the  protein  and  minerals. 

The  analyses  of  giant  brome  grass — samples  10  to  14 — taken  from 
Berkeley  and  Shingle  Springs,  show  the  same  trend  of  decrease  in 
protein  and  ash  with  increase  in  fiber  when  the  plants  cure.  The 
calcium  and  phosphorus  content  is  somewhat  higher,  however,  than 
that  in  the  Merced  grasses. 

The  series  of  analyses  on  soft  chess  or  cheat — samples  15  to  18 — 
are  interesting  in  that  sample  18  had  been  exposed  all  summer  and 
to  numerous  rains  in  the  fall.  It  is  generally  recognized  that  a  rain, 
after  the  forage  drys,  spoils  the  feed.  A  comparison  of  this  forage 
with  samples  16  and  17,  collected  in  August  and  October  and  not 
exposed  to  rain,  shows  very  little  change  in  amount  of  protein,  a 
decrease  in  the  already  small  quantity  of  fat,  a  slight  decrease  in  the 
nitrogen-free  extract  and  a  small  increase  in  fiber.  Unfortunately 
analyses  for  calcium  and  phosphorus  are  not  available,  but  the  total 
ash  (not  given  in  the  table)  decreased  from  8.26  per  cent  in  August 
to  4.10  per  cent  in  January. 


38  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

It  is  obvious  that  dry  range  grasses  are  deficient  in  protein,  and 
the  first  consideration  of  the  stockman  who  is  desirous  of  maintain- 
ing his  cow  herd  in  the  strong  condition  necessary  for  efficient 
reproduction  should  consist  in  making  good  this  deficiency.  Cotton- 
seed cake  will  meet  this  requirement  and  is  also  high  in  phosphorus, 
but  with  its  increasing  demand  other  high  protein  feeds  may  become 
more  economical. 

When  cattle  are  confined  to  dried  grasses,  such  as  wild  oats, 
bromes,  etc.,  about  2  pounds  of  cottonseed  cake  daily  will  be  necessary 
to  furnish  an  adequate  supply  of  protein  for  a  1,000  pound  animal, 
although  a  smaller  quantity  will  be  decidedly  beneficial. 

From  the  results  of  the  digestion  trial  by  Mead  and  Guilbert 
previously  mentioned,  table  5  is  presented  showing  the  requirements 
of  a  1,000  pound  beef  cow  in  calf,  the  amount  of  nutrients  supplied 
by  the  dry  range  grass  used  in  the  trial  and  how  the  deficiency  in 
protein  is  met  by  cottonseed  meal.  The  nutritive  requirements  given 
in  the  table  are  calculated  to  allow  for  some  gain  in  weight. 

TABLE  5 

Eequirements  of  a  1,000  Pound  Beef  Cow  in  Calf  (Morrison  Standards)  and 

Amount  of  Nutrients  Furnished  by  25  Pounds  of  Dry  Kange 

Grass  and  2  Pounds  of  Cottonseed  Cake 


Protein, 
pounds 

Total  digestible 
nutrients,  pounds 

Requirement  of  a  1,000-pound  beef  cow  in  calf 

0  7-0.9 
None 
0.74 

9.0-12.0 

11.11 

1.56 

Total 

0.74 

12.67 

The  figures  in  the  table  indicate  that  if  the  cow  can  obtain  25 
pounds  of  the  grass  daily  the  energy  requirement  for  maintenance 
will  be  met  but  she  will  get  little  or  no  protein.  The  two  pounds  of 
cottonseed  cake  will  meet  the  minimum  protein  requirement  and, 
besides,  furnish  additional  energy  for  gain  in  weight. 

The  most  desirable  method  for  feeding  supplemental  concentrates 
on  the  range  is  to  feed  the  cattle  wherever  they  happen  to  be  grazing, 
as  cattle  fed  in  this  way  are  less  disturbed  and  spend  less  time  away 
from  grazing  than  if  they  are  fed  in  a  central  place.  Moreover,  better 
distribution  of  cattle  on  the  range  is  maintained  and  less  time  is  spent 
in  traveling  over  areas  where  feed  is  depleted.  On  very  poor  quality 
roughage,  feeding  of  small  quantities  of  concentrate  may  have  a  slight 
tendency  to  decrease  the  amount  of  range  forage  consumed.   However, 


Bul.  458]  PERCENTAGE   OF   CALF    CROP   IN   RANGE   HERDS  39 

the  amount  of  the  concentrate  fed  is  so  small  that  it  is  not  reasonable 
(o  believe  that  it  would  affect  the  appetite  materially,  and  very  good 
evidence  is  available  showing  increase  in  feed  consumption  where  the 
ration  is  well  balanced,  compared  to  a  deficient  ration.  Limited  hay 
feeding  on  the  other  hand  more  nearly  satisfies  the  animal's  desire 
for  bulk  and  probably  has  a  greater  effect  on  cutting  down  the  "rust- 
ling" tendencies  of  the  stock,  consequently  the  utilization  of  range 
feed.  When  cake  is  fed  on  the  ground  it  will  pay  to  screen  out  the 
fine  material,  which  results  in  saving  5-15  per  cent  of  this  material 
for  feeding  in  troughs.  The  most  efficient  results  from  supplementary 
feeding  come  from  supplying  the  nutrients  which  are  most  lacking 
in  the  range  forage. 

Bone  meal  can  be  fed  in  troughs  in  the  same  manner  as  salt  is 
commonly  given.  High  grade  steamed  bone  meal  which  is  finely 
ground  should  be  used.  The  appetite  of  the  animal  is  the  best  index 
at  present  available  as  to  whether  or  not  additional  calcium  or  phos- 
phorus is  needed,  both  of  which  are  supplied  by  bone  meal. 

From  the  foregoing  general  discussion,  it  must  be  recognized  that 
a  great  deal  more  investigational  work  will  be  necessary  to  ascertain 
the  areas  in  California  on  which  natural  feeds  during  a  part  or  all 
of  the  year  may  be  lacking  in  essential  dietary  factors.  There  is  great 
need  for  a  method  by  which  an  examination  of  blood,  milk,  or  some 
other  body  fluid  would  give  information  on  the  stage  of  mineral 
metabolism  in  a  group  of  animals.  The  actual  mineral  and  other 
nutritive  content  of  the  most  important  range  grasses  in  various  parts 
of  the  state  over  a  series  of  years  is  needed.  With  this  knowledge,  the 
employment  of  supplemental  feed  could  be  carried  out  more  effect- 
ively and  profitably.  It  must  be  recognized  that  conditions  in  a  single 
locality  vary  from  year  to  year,  depending  on  climatic  conditions. 
Considerable  capital  outlay  for  supplemental  feed  may  be  necessary 
one  year,  with  practically  none  on  another  year.  Many  of  these  Gon- 
dii ions  would  be  automatically  met  if  ranges  were  stocked  with  no 
greater  number  of  cattle  than  could  be  carried  through  in  good  con- 
dition in  poor  years.  Where  it  is  economically  necessary  to  stock 
ranges  to  capacity  on  good  years,  meeting  the  adverse  conditions  on 
poor  years  is  essential . 


/ 


40  UNIVERSITY   OF    CALIFORNIA EXPERIMENT    STATION 


SUMMARY 

1.  Cost  of  production  studies  have  shown  that  the  percentage  calf 
crop  is  a  very  important  factor  in  economical  beef  production. 

2.  Various  factors  have  long  been  recognized  as  influencing  the 
calf  crop  among  which  may  be  mentioned : 

The  plane  of  nutrition  of  the  animals. 

The  season  of  breeding. 

The  proportion  of  males  to  females. 

The  distribution  of  males  and  females  on  the  range. 

Bovine  infectious  abortion. 

Selection  of  breeding  stock  by  proper  culling. 

3.  Evidence  is  presented  to  show  that  failure  to  conceive  is  a  more 
important  factor  than  abortion,  in  the  range  area. 

4.  Failure  to  conceive  has  been  shown  to  be  often  due  to  the  exist- 
ence of  a  faulty  plane  of  nutrition  resulting  in  a  lack  of  proper 
functioning  of  the  ovary  and  no  manifestation  of  heat  periods.  It 
has  been  observed  in  cattle  in  various  parts  of  the  world.  Evidence 
of  a  similar  character  has  been  observed  in  wild  animals  in  their 
native  habitats. 

5.  A  suboptimum  plane  of  nutrition  in  bulls  may  result  in  reduced 
breeding  activity  or  fertility,  or  both. 

6.  Evidence  during  the  past  few  years  has  accumulated  showing 
that  failure  to  conceive  is  at  least  in  part  due  to  restricted  mineral 
intake  with  the  food,  particularly  involving  calcium  and  phosphorus. 

7.  It  is  also  recognized  that  a  deficiency  of  minerals  under  range 
conditions  is  associated  with  low  protein  intake. 

8.  In  general  low  mineral  content  of  feed  is  associated  with  defi- 
cient soil  content  of  the  same  mineral  elements. 

9.  The  extent  of  the  manifestation  of  deficiency  depends  on 
climatic  conditions  which  vary  the  length  of  time  the  animals  are  on 
dry  feed. 

10.  Cows  that  have  weaned  calves  in  the  fall  and  are  again  preg- 
nant must  usually  gain  during  the  early  winter  season  if  they  are  to 
be  at  a  normal  weight  by  the  next  calving  time.  Frequently  they 
have  poor  feed  at  this  time  and  lose  weight. 

11.  While  bone  craving  and  other  forms  of  depraved  appetite  are 
evidences  of  advanced  stages  of  nutritional  deficiency  the  animal  may 
be  in  a  suboptimum  stage  of  nutrition  without  showing  these  symp- 
toms. 


BUL.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  41 

s  12.  The  disturbed  rhythmic  functioning  of  the  ovary  is  one  of  the 
most  delicate  evidences  of  impaired  physiological  function  due  to  a 
lowered  plane  of  nutrition.  This  is  most  likely  to  be  manifested  in 
seasons  of  drought,  with  prolonged  maintenance  on  dry  and  sparse 
feed.  Under  these  conditions  mineral  and  protein  supplements  are 
most  necessary  to  maintain  the  normal  functions  of  the  animals. 
y  13.  Bone  meal  offers  the  most  desirable  mineral  supplement,  and 
from  present  knowledge  the  appetite  of  the  animal  for  this  material 
offers  the  best  available  index  of  need  for  it. 

14.  Any  protein  concentrate  such  as  cottonseed  cake  that  is 
economically  available  may  be  used  to  supplement  the  range  feed. 
The  principal  difference  between  good  and  poor  range  feed  is  in  the 
mineral  and  protein  content. 


ACKNOWLEDGMENT 

The  writers  wish  to  express  their  appreciation  for  the  assistance 
given  by  Mr.  H.  W.  Allinger,  of  the  Division  of  Chemistry,  in  carry- 
ing out  the  analytical  work,  and  to  Mr.  Wm.  H.  Alison,  Jr.,  Assistant 
County  Agent  in  Merced  County,  for  assistance  in  collecting  samples 
of  range  feed. 


LITERATURE  CITED 
i  Adams,  R.  L. 

1924.  The  results  of  a  survey  to  determine  the  cost  of  producing  beef  in 

California.     California  Agr.   Exp.   Sta.   Cir.  281:1-22. 

2  Eckles,  C.  H.,  R.  B.  Becker,  and  L.  S.  Palmer. 

1926.     A  mineral  deficiency  in  the  rations  of  cattle.     Minnesota  Agr.  Exp. 
Sta.  Bui.  229:1-49. 

3  Elliott,  W.  E.,  J.  B.  Orr,  and  T.  B.  Wood. 

1926.     Investigation  on  the  mineral  content  of  pasture  grass  and  its  effect 
on  herbivora.     Jour.  Agr.  Sci.  16:59-104. 
*  Elliott,  W.  E.,  J.  B.  Orr,  and  T.  B.  Wood. 

1925.  Mineral  content  of  pastures.     Scottish  Jour.  Agr  Vol.  8,  No.  4. 
s  Emmerich,  R.  and  O.  Loew. 

1915.     tiber  den  Einfluss  der  Calcium  zer  fuhr  auf  die  Fortpflanzung. 
Landwirtschaftliche  Jahrbucher  48-313-330. 
e  Evans,  H.  M. 

1922.     On   the   relation    between    fertility    and    nutrition.     Jour.    Med.    Re- 
search.    1:319-333,  335-356. 
7  Haring,  C.  M. 

1922.  The  influence  of  diet  on  certain  diseases  of  cattle.  Proc.  Vet. 
Practitioners'  Week.  Jan.  1922.  pp.  89-102.  Univ.  Farm, 
Davis,  Calif. 


42  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

s  Hart,  E.  B.,  B.  A.  Beach,  E.  J.  Delwiche  and  E.  G.  Bailey. 

1927.  Phosphorus  deficiency  and  a  dairy  cattle  disease.     Wis.  Agr.  Exp. 

Sta.  Bui.  389:1-10. 

o  Hart,  E.  B.,  H.  Steenbock,  C.  A.  Elvehjem,  and  J.  Waddell. 

1928.  Copper  as  an  anemia  preventive.    Abst.  of  original  Science  supple- 

ment.    Vol.  67X. 

io  Hart,  E.  B.,  H.  Steenbock  and  G.  C.  Humphrey. 

1920.     Effect   of   rations   restricted   to   the   oat   plant   on   reproduction   in 
cattle.     Wis.  Agr.  Exp.  Sta.  Eesearch  Bui.  49:1-22. 

11  Hart,  E.  B.,  H.  Steenbock,  H.  Scott  and  G.  C.  Humphrey. 

1927.     Influence  of  ultra  violet  light  upon  calcium  and  phosphorus  meta- 
bolism in  milking  cows.     Jour.  Biol.   Chem.  73:59-67. 

i 2  Hilts,  Walter  H. 

1925.     A   study   of   the   1924  calf   crop   in   Nevada.     Nev.   Agr.   Ext.   Cir. 
57:1-10. 

13  Huxley,  Julian. 

1927.     Mice  and  men.     Harpers  Magazine.     156:42-50. 

14  Klemmedson,  G.  S. 

1924.  An  economic  study  of  the  costs  and  methods  of  range  cattle  pro- 

duction on  forty-one  ranches  in  Colorado,  1922.  Preliminary 
Report  of  the  Colorado  Agricultural  Experiment  Station  and 
the  U.  S.  Department  of  Agriculture,  Bureau  of  Agricultural 
Economics  and  Bureau  of  Animal  Industry,  cooperating,  pp. 
1-34.     (mimeographed.) 

is  Kramer,  B.  and  J.  Howland. 

1922.     Bui.  Johns  Hopkins  Hosp.  33,  pp.  313-326. 

is  McHargue,  J.  S. 

1927.     The  significance  of  small  amounts  of  inorganic  elements  in  plants. 
Abst.  Proc.  1st  Internat.  Cong,  of  Soil  Sci.  Fourth  Com.    pp.  7-8. 
17  Orr,  J.  B. 

1924.     The  influence  of  nutrition  on  the  incidence  of  disease.     The  Vet- 
erinary   Record,     Reprint    Rowett    Res.     Inst,     collected    papers. 
1:523-535. 
J  s  Orr,  J.  B. 

1925.  The  importance  of  mineral  matter  in  nutrition.     Rowett  Res.  In- 

stitute, collected  papers,  1:189-215. 

is  Palmer,  L.  S.  and  C.  H.  Ecki.es. 

1927.  Effect  of  phosphorus  deficient  rations  on  blood  composition.  Proc. 
Soc.  Exp.  Biol,  and  Med.  24:307-309. 

20  Parr,  V.  V.,  and  G.  S.  Klemmedson. 

1924.  An  economic  study  of  the  costs  and  methods  of  range  cattle  pro- 
duction in  the  northeastern  range  area  of  Texas,  1920,  1921, 
1922.  Preliminary  report  of  the  U.  S.  Department  of  Agricul- 
ture, Bureau  of  Agricultural  Economics  and  Bureau  of  Animal 
Industry,   cooperating,     pp.   1-24.      (mimeographed.) 


Bul.  458]  PERCENTAGE   OF    CALF    CROP   IN   RANGE   HERDS  4'J 

21  Parr,  V.  V.,  and  G.  S.  Klemmedson. 

1925.  An  economic  study  of  the  costs  and  methods  of  range  cattle  pro- 
duction in  north  central  Texas.  Preliminary  report  of  U.  S. 
Department  of  Agriculture,  Bureau  of  Agricultural  Economics 
and  Bureau  of  Animal  Industry,  cooperating,  pp.  1-39.  (mimeo- 
graphed.) 

22  Potter,  E.  L. 

1921.  Western  live-stock  management.  The  MacMillan  Co.,  New  York, 
1-462. 

23  Potter,  E.  L. 

1925.  Cost  of  producing  beef  on  the  ranges  of  eastern  Oregon.     Oregon 

Agri.  Exp.  Sta.  Bui.  220:1-22. 

24  Potter,  G.  M. 

1920.  Field  observations  in  the  control  of  abortion  disease.  Jour,  of  the 
Amer.  Vet.  Med.  Assoc.  10,   (2):152. 

25  Schmidt,  H. 

1926.  Feeding  bone  meal  to  range  cattle  on  the  coastal  plains  of  Texas. 

Texas  Agr.  Exp.  Sta.  Bui.  344:1-37. 

26  Theiler,  Sir  Arnold. 

1920.  The  cause  and  prevention  of  lamsiekte.  Jour,  of  Dept.  of  Agr., 
Union  of  South  Africa,  Eeprint  13:1-25. 

27  Theiler,  Sir  Arnold,  H.  H.  Green  and  P.  J.  Du  Toit. 

1924.  Phosphorus  in  the  live  stock  industry.  Jour,  of  Dept  of  Agr., 
Union  of  South  Africa,  Eeprint  18:1-47. 

28  Theiler,  Sir  Arnold,  et  al. 

1927.  11th   and   12th   Reports   of  the  Director   of  Veterinary   Education 

and  Research,  Pt.  II,  Dept  of  Agriculture,  Union  of  South  Africa, 
1-1361. 

29  Theiler,  Sir  Arnold,  H.  H.  Green  and  P.  J.  Du  Toit. 

1927.     Minimum     mineral     requirements     in     cattle.        Jour.     Agr.     Sci. 
17:291-314. 

so  Theiler,  Sir  Arnold,  H.  H.  Green  and  P.  J.  Du  Toit. 

1928.  Studies   in   mineral   metabolism.      IIT.    Breeding    of   cattle   on   phos- 

phorus deficient  pasture.     Jour.  Agri.  Sci.  18,  3:369-371. 
si  Tuff,  Per. 

1923.  Osteomalacia    and    its    occurrence    in    cattle    in    Norway.      Proc. 

World's  Dairy  Congress,  2:1494-1501. 

-  Walker,  A.  L.,  and  J.  L.  Lantow. 

1927.  A  preliminary  study  of  127  New  Mexico  ranches  in  1925.  New 
Mexico  Agr.  Exp.  Sta.  Bui.  159:1-107. 

33  Welch,  Howard. 

1924.  Bone  chewing  by  cattle.     Montana  Agr.  Exp.  Sta.  Cir.  122:1-8. 


STATION   PUBLICATIONS  AVAILABLE   FOR  FREE   DISTRIBUTION 


BULLETINS 


No.  No. 

253.   Irrigation   and    Soil   Conditions   in    the  389. 

Sierra    Nevada   Foothills,    California.  390. 

262.  Citrus   Diseases  of   Florida   and   Cuba 

Compared   with   those  of   California.  391. 

263.  Size  Grades  for  Ripe  Olives. 

268.   Growing  and  Grafting  Olive  Seedlings.  392. 

277.  Sudan  Grass.  393. 

278.  Grain   Sorghums.  394. 

279.  Irrigation   of   Rice  in   California. 
283.  The  Olive  Insects  of  California. 

304.  A  Study  of  the  Effects  of  Freezes  on  395. 

Citrus  in  California. 

310.   Plum  Pollination.  396. 

313.   Pruning      Young      Deciduous      Fruit 

Trees.  397. 

324.   Storage  of  Perishable  Fruits  at  Freez- 
ing Temperatures.  398. 

328.    Prune    Growing  in    California.  400. 

331.  Phylloxera-resistant  Stocks.  402. 

335.   Cocoanut   Meal    as   a    Feed   for    Dairy  404. 

Cows  and   Other   Livestock.  405. 

340.   Control     of     the     Pocket     Gopher     in  406. 

California.  407. 

343.  Cheese   Pests  and  Their   Control. 

344.  Cold   Storage   as   an    Aid   to   the   Mar- 

keting of  Plums,  a  Progress  Report.  408. 

347.  The  Control  of  Red  Spiders  in  Decid-  409. 

uous  Orchards. 

348.  Pruning  Young  Olive  Trees. 

349.  A    Study    of    Sidedraft    and    Tractor 

Hitches.  410. 

350.  Agriculture      in      Cut-Over      Redwood 

Lands. 

353.  Bovine    Infectious    Abortion,    and    As-  411. 

sociated  Diseases  of  Cattle  and  New- 
born  Calves.  412. 

354.  Results  of  Rice  Experiments  in  1922. 

357.  A    Self-Mixing    Dusting    Machine    for 

Applying  Dry  Insecticides  and  Fun-  414. 

gicides. 

358.  Black    Measles,     Water    Berries,     and  415. 

Related  Vine  Troubles.  416. 

361.  Preliminary  Yield  Tables  for   Second- 

Growth   Redwood.  417. 

362.  Dust  and   the   Tractor   Engine. 

363.  The   Pruning  of  Citrus  Trees  in   Cali-  418. 

fornia. 

364.  Fungicidal    Dusts    for    the    Control    of  419. 

Bunt. 

366.  Turkish     Tobacco     Culture,     Curing,  420. 

and   Marketing. 

367.  Methods  of  Harvesting  and  Irrigation  421. 

in  Relation  to  Moldy  Walnuts.  422. 

368.  Bacterial      Decomposition      of      Olives 

During  Pickling.  423. 

369.  Comparison     of     Woods     for     Butter 

Boxes.  424. 

370.  Factors    Influencing   the    Development 

of  Internal  Browning  of  the  Yellow  425. 

Newton  Apple.  426. 

371.  The    Relative    Cost    of   Yarding    Small 

and  Large  Timber.  427. 

373.  Pear   Pollination. 

374.  A    Survey    of    Orchard    Practices    in  428. 

the     Citrus     Industry     of     Southern 
California. 

375.  Results   of    Rice   Experiments   at   Cor-  429. 

tena,   1923,  and  Progress  in  Experi-  430. 

ments  in  Water  Grass  Control  at  the  431. 

Biggs   Rice  Field    Station,    1922-23. 
377.   The  Cold  Storage  of  Pears.  432. 

380.   Growth    of    Eucalyptus    in    California 

Plantations.  433. 

382.   Pumping    for    Draininge    in    the    San 

Joaquin    Valley,    California.  434. 

385.  Pollination  of  the  Sweet  Cherry. 

386.  Pruning     Bearing     Deciduous     Fruit  435. 

Trees. 

387.  Fig   Smut. 

388.  The   Principles   and   Practice   of    Sun- 

Drying  Fruit. 


Berseem  or  Egyptian  Clover. 

Harvesting  and  Packing  Grapes  in 
California. 

Machines  for  Coating  Seed  Wheat 
with    Copper   Carbonate   Dust. 

Fruit  Juice  Concentrates. 

Crop   Sequences  at  Davis. 

I.  Cereal  Hay  Production  in  Cali- 
fornia. II.  Feeding  Trials  with 
Cereal  Hays. 

Bark  Diseases  of  Citrus  Trees  in  Cali- 
fornia. 

The  Mat  Bean,  Phaseolus  Aconitifo- 
lius. 

Manufacture  of  Roquefort  Type  Cheese 
from  Goat's  Milk. 

Orchard    Heating  in   California. 

The   Utilization  of  Surplus  Plums. 

The   Codling  Moth   in  Walnuts. 

The  Dehydration  of  Prunes. 

Citrus   Culture   in    Central    California. 

Stationary  Spray  Plants  in  California. 

Yield,  Stand,  and  Volume  Tables  for 
White  Fir  in  the  California  Pine 
Region. 

Alternaria  Rot  of  Lemons. 

The  Digestibility  of  Certain  Fruit  By- 
products as  Determined  for  Rumi- 
nants. Part  I.  Dried  Orange  Pulp 
and  Raisin  Pulp. 

Factors  Influencing  the  Quality  of 
Fresh  Asparagus  after  it  is  Har- 
vested. 

Paradichlorobenzene  as  a  Soil  Fumi- 
gant. 

A  Study  of  the  Relative  Value  of  Cer- 
tain Root  Crops  and  Salmon  Oil  as 
Sources   of   Vitamin    A   for   Poultry. 

Planting  and  Thinning  Distances  for 
Deciduous  Fruit  Trees. 

The  Tractor  on   California  Farms. 

Culture  of  the  Oriental  Persimmon  in 
California. 

Poultry  Feeding:  Principles  and  Prac- 
tice. 

A  Study  of  Various  Rations  for  Fin- 
ishing Range  Calves    as  Baby  Beeves. 

Economic  Aspects  of  the  Cantaloupe 
Industry. 

Rice  and  Rice  By-Products  as  Feeds 
for  Fattening  Swine. 

Beef   Cattle  Feeding  Trials,    1921-24. 

Cost  of  Producing  Almonds  in  Cali- 
fornia: a  Progress  Report. 

Apricots  (Series  on  California  Crops 
and  Prices). 

The  Relation  of  Rate  of  Maturity  to 
Egg  Production. 

Apple  Growing  in  California. 

Apple  Pollination  Studies  in  Cali- 
fornia. 

The  Value  of  Orange  Pulp  for  Milk 
Production. 

The  Relation  of  Maturity  of 
fornia  Plums  to  Shipping 
Dessert  Quality. 

Economic  Status  of  the  Grape  Industry. 

Range  Grasses  of  California. 

Raisin  By-Products  and  Bean  Screen- 
ings as  Feeds  for  Fattening  Lambs. 

Some  Economic  Problems  Involved  in 
the  Pooling  of  Fruit. 

Power  Requirements  of  Electrically 
Driven     Manufacturing    Equipment. 

Investigations  on  the  Use  of  Fruits  in 
Ice  Cream  and  Ices. 

The  Problem  of  Securing  Closer 
Relationship  Between  Agricultural 
Development  and  Irrigation  Con- 
struction. 


Cali- 
and 


bulletins- 
no. 

436.  I.   The   Kadota   Fig.      II.   Kadota   Fig 

Products. 

437.  Economic    Aspects    of    the    Dairy    In- 
dustry. 

Grafting  Affinities  with  Special  Refer- 
ence to  Plums. 

The  Digestibility  of  Certain  Fruit  By- 
products as  Determined  for  Rumi- 
nants. Part  II.  Dried  Pineapple 
Pulp,  Dried  Lemon  Pulp,  and  Dried 
Olive  Pulp. 

The  Feeding  Value  of  Raisins  and 
Dairy  By-Products  for  Growing  and 
Fattening  Swine. 

The  Electric  Brooder. 

Laboratory  Tests  of  Orchard  Heaters. 

Standardization  and  Improvement  of 
California   Butter. 

Series  on  California  Crops  and  Prices: 
Beans. 


■{Continued) 
No. 
445. 


438. 
439. 


440. 


441. 
442. 
443. 

444. 


Economic  Aspects  of  the  Apple  In- 
dustry. 

The  Asparagus  Industry  in  California. 

The  Method  of  Determining  the  Clean 
Weights  of  Individual  Fleeces  of 
Wool. 

Farmers'  Purchase  Agreement  for 
Deep   Well   Pumps. 

449.  Economic   Aspects  of  the  Watermelon 

Industry. 

450.  Irrigation     Investigations    with    Field 

Crops  at  Davis,  and  at  Delhi,   Cali- 
fornia. 

451.  Studies   Preliminary   to   the    Establish- 

ment of  a  Series  of  Fertilizer  Trials 
in  a  Bearing  Citrus  Grove. 
Economic    Aspects    of    the    Pear    In- 
dustry. 


447. 


448. 


452. 


CIRCULARS 

No.  No. 

87.   Alfalfa.  265. 

117.  The    selection    and    Cost    of    a    Small  266. 

Pumping   Plant. 

127.   House  Fumigation.  267. 
129.  The  control  of  Citrus  Insects. 

136.   Melilotus    Indica    as    a    Green-Manure  269. 

Crop  for  California.  270. 

144.   Oidium    or    Powdery    Mildew    of    the  273. 

Vine.  276. 

157.   Control   of  Pear   Scab.  277. 
164.   Small   Fruit   Culture   in    California. 

166.  The  County  Farm   Bureau.  278. 
178.  The  Packing  of  Apples  in  California. 

202.  County    Organization    for    Rural    Fire  279. 

Control. 

203.  Peat   as   a  Manure   Substitute.  281. 
209.  The  Function  of  the  Farm  Bureau. 

212.   Salvaging  Rain-Damaged   Prunes. 

215.  Feeding  Dairy  Cows  in   California.  282. 

230.  Testing  Milk,    Cream,    and   Skim  Milk 

for  Butterfat.  284. 

231.  The  Home  Vineyard.  286. 

232.  Harvesting    and    Handling    California  287. 

Cherries    for   Eastern    Shipment.  288. 

234.  Winter     Injury     to     Young     Walnut  289. 

Trees  During  1921-1922.  290. 

238.  The   Apricot  in   California.  292. 

239.  Harvesting     and     Handling     Apricots  293. 

and  Plums  for  Eastern  Shipment.  294. 

240.  Harvesting    and    Handling    California  296. 

Pears  for  Eastern  Shipment. 

241.  Harvesting    and    Handling    California  298. 

Peaches  for  Eastern   Shipment. 

243.  Marmalade     Juice     and     Jelly     Juice  300. 

from  Citrus  Fruits.  301. 

244.  Central  Wire  Bracing  for  Fruit  Trees.  302. 

245.  Vine  Pruning  Systems.  304. 

248.  Some   Common   Errors  in   Vine   Prun-  305. 

ing  and  Their  Remedies.  307. 

249.  Replacing  Missing  Vines.  308. 

250.  Measurement   of   Irrigation   Water   on  309. 

the  Farm.  310. 

252.  Support   for   Vines. 

253.  Vineyard   Plans.  311. 
255.   Leguminous    Plants    as    Organic    Fer-  312. 

tilizers  in    California   Agriculture. 

257.  The  Small-Seeded   Horse  Bean    (Vicia 

faba   var.   minor). 

258.  Thinning   Deciduous   Fruits. 

259.  Pear  By-Products. 
261.   Sewing  Grain  Sacks. 


Plant   Disease  and   Pest  Control. 

Analyzing  the  Citrus  Orchard  by 
Means  of  Simple  Tree  Records. 

The  Tendency  of  Tractors  to  Rise  in 
Front;  Causes  and  Remedies. 

An   Orchard   Brush   Burner. 

A  Farm  Septic  Tank. 

Saving  the  Gophered  Citrus  Tree. 

Home   Canning. 

Head,  Cane  and  Cordon  Pruning  of 
Vines. 

Olive  Pickling  in  Mediterranean 
Countries. 

The  Preparation  and  Refining  of 
Olive  Oil  in   Southern  Europe. 

The  Results  of  a  Survey  to  Deter- 
mine the  Cost  of  Producing  Beef  in 
California. 

Prevention  of  Insect  Attack  on  Stored 
Grain. 

The  Almond  in   California. 

Milk  Houses  for  California  Dairies. 

Potato   Production  in   California. 

Phylloxera  Resistant  Vineyards. 

Oak  Fungus  in   Orchard  Trees. 

The  Tangier  Pea. 

Alkali   Soils. 

The    Basis   of    Grape    Standardization. 

Propagation    of  Deciduous  Fruits. 

Control  of  the  California  Ground 
Squirrel. 

Possibilities  and  Limitations  of  Coop- 
erative Marketing. 

Coccidiosis  of  Chickens. 

Buckeye  Poisoning  of  the  Honey  Bee. 

The   Sugar  Beet  in   California. 

Drainage  on  the  Farm. 

Liming  the   Soil. 

American   Foulbrood   and   Its  Control. 

Cantaloupe    Production   in    California. 

Fruit  Tree  and   Orchard  Judging. 

The  Operation  of  the  Bacteriological 
Laboratory  for  Dairy  Plants. 

The  Improvement  of  Quality  in  Figs. 

Principles  Governing  the  Choice,  Op- 
eration and  Care  of  Small  Irrigation 
Pumping   Plants. 


The  publications  listed  above  may  be  had  by  addressing 

College  of  Agriculture, 

University  of  California, 

Berkeley,  California. 


[2m-9'28 


